


In Your Mind

by fireworksinthenight



Category: Teenage Mutant Ninja Turtles (TV 2012), Teenage Mutant Ninja Turtles - All Media Types
Genre: Family, Gen, Humor, Supernatural Elements
Language: English
Status: Completed
Published: 2019-03-27
Updated: 2019-06-16
Packaged: 2019-12-25 12:05:54
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 13
Words: 20,442
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/18260939
Author URL: https://archiveofourown.org/users/fireworksinthenight/pseuds/fireworksinthenight
Summary: Leo's attempt at perfecting his healing skills has an unexpected result, and now he relies on Mikey to help him - preferably before their whole family gets destroyed.





	1. Prologue

**Author's Note:**

> _A persistent plot bunny._   
>  _2012 turtles. Everybody in here, but Leo-centric with lots and lots of Mikey, for reasons which will become obvious at the end of this prologue._   
>  _I don't own any turtles._

Everything was silent in the lair. It was well past everybody's bedtime, and even Donnie had left his current pet project for the time being and found his way back to his bed.

Yes, everything was silent, peaceful and quiet, which meant it was the perfect time for Leo to implement his plan.

With a grin, the blue-masked turtle silently reached for the flashlight under his pillow and switched it on. The door was closed and if he stayed under his heavy quilt, the light would be invisible from outside.

Leo grabbed the scroll that he had borrowed from his father's shelves and looked at it lovingly.

There, written on the parchment, were the symbols that Splinter was teaching him - the symbols which, when whispered and signed, could help a body to heal.

He began reading the title - a title he already knew.

_Fracture Fixation Mantra_

It was such useful knowledge to have, he didn't understand why Splinter hadn't wanted him to learn it at once. His father was helping him to develop his healing skills, but he had refused to teach him this particular mantra. And he had given no explanation for that decision.

Leo hadn't dared to insist, but his curiosity had been too strong.

 _I'm just getting ahead,_ he thought, fighting his feeling of guilt.

He didn't like going behind his father's back, but it was an important matter.

If he had known about this mantra sooner… If he had known that he had healing hands when he had woken up in a bathtub after months in a coma…

Maybe his recovery would have been faster. Maybe he wouldn't have felt so helpless, so useless, when each step was slow and painful, and he could see the concern he was causing his family…

 _It made me stronger,_ he reminded himself.

Nevertheless, he was going to do everything in his power so it never happened again.

Taking a deep breath, Leo began following the instructions written on the parchment, his three-fingered hands moving in rhythm to match his words.

_Rin… Pyo…_

So far, so good.

_Zen… Rin…_

The scroll was long, and Leo kept reading it stubbornly by lamplight, even as his eyelids grew heavier and heavier and his movements became sloppier. Maybe it wasn't such a good idea after all, he had been very busy tonight - training, watching TV, training again, patrolling… - and he needed his rest.

_Keep going…_

_Rizen, Pyotushai, Kiorin…_ Leo obediently went on, before shaking his head. _Urgh. No, that's not it. Do it again._

 _No, keep going,_ his mind insisted.

His mind?

 _Pyorizenkio… I'm barely awake,_ Leo protested.

Somewhere in his fuzzy brain, a red light had turned on.

_Just a little more. Kai…Shah…Toh…_

_Kai, Shah, Toh,_ Leo obediently repeated. Before he snapped awake and spoke aloud.

"Wait a minute! Who are you?"

 _It won't matter to you anymore,_ the voice whispered joyfully. _Thank you. It has been a long time._

Leo wanted to protest, but excruciating pain coursed through his body, and he felt torn apart - _literally…_

"Leo, are you awake?"

 _Mikey,_ Leo thought. He held on to the familiar voice, and the pain receded.

Somebody laughed softly.

"How does it look like?"

"Leo, I had a nightmare about Karai," Mikey said shyly. "She was coming back to hurt us."

Leo immediately wanted to reassure him, but he couldn't talk. He tried to inhale deeply, but he couldn't breathe. And what he could see made no sense… What he could see was…

"Ridiculous. Go back to sleep."

"But Leo!"

If he focused, he could feel his brother's emotions - lack of understanding and hurt, why was Leo dismissing him?

_Mikey, no! Mikey, I'm here!_

But his brother wasn't hearing him.

"Goodnight, Mikey," the voice - _his voice_ \- said, and Leo watched helplessly through Mikey's eyes as his own body winked, turned over and switched off the flashlight.


	2. Monologues

_Don't panic. Don't panic. You fell asleep and you're dreaming. It's a nightmare, it has to be. Wake up, Leo! Wake up!_

Despite his frantic thoughts, Leo wasn't optimistic. The pain had felt too real, and the part of his brain which was always capable of cold analysis of desperate situations had already reported its findings.

Somebody - something? - had taken over his body, and he was stuck in his brother's mind.

A brother who was now dejectedly looking down, if the ground and the feet in Leo's field of vision were any indication.

Or Mikey's field of vision, to be more precise.

 _Mikey?_ Leo tried again. _Mikey, can you hear me?_

He obtained no answer. He could feel the sadness radiating from his brother, though, as he walked away from Leo's room after having been let down by the being he thought was Leo.

The real Leo was feeling angrier by the minute, both at the thing that had targeted him - a thing that was now sleeping or plotting in his bed or whatever it was that things like that did once they possessed a new body - and at himself for being so stupidly careless.

_Why did I have to read that scroll tonight? Why didn't I wait for Master Splinter to explain it to me? This is messed up. This is messed up so badly, Raph will never leave it down…_

Leo found himself praying that his brother would have the opportunity to laugh at him about it. The sooner, the better.

He half-expected Mikey to knock at Donnie or Raph's door, but the feet kept walking towards - towards…

_The kitchen?_

He saw an arm rise to open the freezer, and soon the meowing of an ice cream cat told him whom Mikey had turned to for comfort.

"Hello, Ice Cream Kitty," Mikey whispered as he gathered his pet in his arms.

Leo didn't feel anything, and he absent-mindedly noted that if he shared Mikey's sight and hearing, he had no access to his sense of touch, or smell.

 _Or taste,_ he added to himself as Mikey licked the cat. _Which is probably for the best, considering what Mikey calls food._

Mikey sat down at the kitchen table, Ice Cream Kitty still in his arms.

"Sorry for disturbing you in the middle of the night," he whispered to his cat. "I had a nightmare."

Ice Cream Kitty meowed and licked Mikey's cheek affectionately, and Leo felt the urge to put his arms around his brother's shell and hug him - except, of course, he couldn't.

"It was about Karai," Mikey went on. "She was poisoning us again, and this time Leo wasn't there and…"

_Mikey-I'm-here-Mikey-no-Mikey-I'll-never-let-her-hurt-you-Mikeyyyyyyyy_

"…and I woke up and I just wanted to make sure Leo was there, you know? And I told him about my dream and I was sure he was going to ask if I wanted to stay with him for a while - but he told me it was ridiculous and goodnight."

Mikey's voice was full of sorrow and Leo wanted to scream in frustration at being unable to reach him when he was so _close_ -

"Maybe I _am_ being ridiculous," Mikey whispered. "It was just a nightmare."

Not the kind of nightmare that let you scream in the middle of the night so that your brothers could rush to your side - all three of them just here for you - and then everything felt easy as they rubbed your skull and put their arms around your shoulders and smiled to you, no, it was the kind of nightmare that left you fighting for breath and unable to speak, until you gathered enough courage to stand up and seek for help in the cold dark hallways of your home and things might very well be lurking in the shadows…

Leo realized he was picking up on Mikey's train of thought and slowly withdrew from it, fighting to keep his feelings under control.

_I'm so, so sorry, Mikey._

"I could have gone to Raph or Donnie, but if Leo laughed at me, they'll probably do it too," Mikey confided, and Ice Cream Kitty looked at him with comprehensive ice cream cat's eyes, and why was his field of vision slightly blurry all of a sudden?

Ice Cream Kitty licked Mikey's cheek again and Mikey buried his face in his pet's body, while Leo began to seriously plot everything he was going to do to the usurper once he had his body back.

Because he _was_ going to retrieve his body, even if he had no idea how he would achieve that. No ill-advised being could kick him out and let his brother think that his feelings didn't matter.

He was so stupid. So stupid for doing what he had done and hoping it would make things better. It was ridiculous, _he_ was ridiculous…

Leo realized he was picking up on Mikey's feelings again.

 _Mikey?_ he whispered, without much hope.

As he had expected, he got no reaction.

 _Mikey, it wasn't me,_ he kept whispering, more for his sake than for his brother. _I would never dismiss you like that. You know that, right? I'm sorry. I'll make things right. Mikey, you're not ridiculous, you're my incredible brother and I would do anything for you. Mikey…_

Leo made sure to let the love he felt wrap around his brother's thoughts - if he couldn't hug him then at least he would try that - and maybe Mikey's subconscious became aware of it, or maybe Ice Cream Kitty's purrs were soothing, Leo didn't know, but Mikey was calming down and opening his eyes and licking Ice Cream Kitty's face.

"It's not like him," he uttered, almost defiantly.

And although Leo was a jumbled mix of emotions and pretty much nothing more right now, these words gave him new hope. That _thing_ had no idea what it had gotten itself into. He and his brothers were so close, of course they were going to suspect something was amiss. And his father would too - and even if Leo would rather have Splinter never knowing what he had managed to do to himself, he would take whatever scolding and punishment his father saw fit if it meant things were back to normal.

_I'll just have to wait until next morning. They will know it's not me in a heartbeat._


	3. Breakfast

**Notes for the Chapter:**

> _A note about names._   
>  _Leo: well, Leo._   
>  _Leonardo: the being swaggering in Leo’s body._

Leo half-expected to lose consciousness when Mikey finally went to sleep, but it wasn't the case. Instead, he was left alone with his thoughts in complete darkness. At least he could listen to Mikey's soft snores. If somebody had told him that one day his brother's snoring would prevent him from going crazy, he would have laughed to their face.

Nevertheless, he was clinging to the sounds as if they were a life preserver. It was proof that he hadn't completely lost his connection to the real world. There was hope for him yet.

He tried to imagine what the imposter had in mind. _It has been a long time,_ he had said. Was he used to possess bodies? Was he an ancient spirit of some kind?

And the most important question of all…

_What will he do to my family?_

Leo had heard stories. Not all spirits were evil. Some just wanted to have fun with mortals, and some were pretty harmless. The one who had stolen his body hadn't been threatening towards Mikey, the night before. But it didn't mean anything.

_Harmless beings don't get rid of people's spirits to use their bodies._

When his brothers would ask him who he was, would demand for him to leave… what would happen?

Leo shivered. His only hope was that the being had needed a body. It probably would take some time for him to get used to it, and even then, he would be limited to what Leo could do.

Which was, in all modesty, a lot. But his brothers had the benefit of numbers, and of course, Master Splinter could beat him blinded and with his little finger.

 _It's going to be fine,_ he attempted to persuade himself.

He tried to focus his thoughts on something else. He didn't dare to meditate for fear of losing his connection to Mikey, and physical exercise was out of the question.

It was frustrating.

In the end, he settled for picturing himself going through his favorite katas, move after move. It wasn't very satisfying, but at least it passed the time.

The night stretched, and Leo was immensely relieved when Mikey opened his eyes again the next morning.

With a groan, his brother switched on his bed lamp. With another groan, he pulled his quilt above his head to shield his eyes from the light. If Leo had been able to, he would have grinned.

_Come on, Mikey, stand up! Breakfast time!_

Mikey groaned again before pushing his quilt away and jumping on his feet. A split second later, he was fully awake and humming to himself.

Leo felt relief overwhelm him. Mikey seemed back to his usual cheerful self.

Mikey opened the door and went to the bathroom. There, Leo discovered to his utter horror that he couldn't avoid seeing what Mikey saw.

And so he watched helplessly as his brother used his urine to draw a bee in the toilet bowl - with impressive accuracy, he had to admit.

That vision was still in his mind when Mikey happily went to the kitchen and began making breakfast. Leo was sure he would never be able to forget it.

A few minutes later, he heard footsteps and groans coming from outside the kitchen.

"Good morning, Raph," Mikey welcomed the newcomer without even turning around to look at him.

A grumble was his only answer.

Mikey was finishing his pancakes when a powerful yawn echoed inside the kitchen, and he turned just in time to see Donnie plop down on a chair.

"Good morning, Dee," Mikey greeted him, giving him the first pancake and sticking his tongue out at Raph, who gave him a murderous look.

Mikey kept his tongue stuck out. He nonetheless hurried to give Raph the second pancake. The sturdy turtle bit it without a word.

"Thanks, Mikey." Donnie yawned. "Hey, where is Leo? Don't tell me he's already in the dojo."

Mikey's face must have fallen a little at the mention of Leo's name, because Donnie looked at him with curiosity. Before he could ask another question, though, Raph talked.

"No, I checked. He must be oversleeping."

"Leo, oversleep?" Donnie chuckled. "I'll have to find my telescope. It must be a blue moon."

 _Hey, I'm right here, Donnie,_ Leo answered for himself. Quite sulkily.

Raph shrugged.

"At least he's resting for once. Have you noticed how hard he has been working lately? And by hard, I mean harder than usual. I'm telling you, he's still feeling guilty about Karai's mutation."

Leo was unsure how to react.

_Are you worrying about me, Raph?_

Donnie frowned.

"I thought he had come to terms with that. It wasn't his fault."

"Don't tell me." Raph took another bite of his pancake. "Tell him."

"Maybe seeing her under Shredder's control again reactivated that guilt," Mikey suggested.

Both Raph and Donnie looked at him with wide eyes.

"That… actually makes sense, Mikey," Donnie acknowledged.

"Of course it does." Mikey puffed himself up.

Maybe Leo hadn't meant what he had said yesterday. Maybe Raph was right and he had been exhausted, and failed to notice Mikey's distress - and maybe Mikey's mind had invented the coldness in his tone. He had a wild imagination, after all.

 _No,_ Leo exclaimed. _Mikey, no, it's not the reason!_

"We have training in half an hour," Raph went on. "If he's not there in ten minutes, I'll wake him up."

"No need to," a fourth voice said. Three sets of eyes and four minds contemplated the turtle who had just spoken. He was blue-masked and had twin katana fastened to his shell.

_There it is. The moment of truth._

Leo watched him - himself - intensely. He didn't always take his weapons with him for breakfast, but it wasn't unheard of, either - it wouldn't be enough to set his brothers thinking.

Leonardo sat down and Mikey gave him a plate.

"Thanks, Mikey," Leonardo said with a smile, and Leo felt Mikey relax.

 _Mikey, don't let him deceive you,_ he pleaded. _He's not me!_

The being knew his brother's name. But it meant nothing, right? He could have eavesdropped on them.

Raph smiled warmly at Leonardo.

"Are you ready for today's training, Leo?"

"Of course," Leonardo replied, returning the grin. "Master Splinter told us that he was going to show us a new secret move! I wouldn't want to miss that for the world."

Leo couldn't believe Mikey's ears. How could the imposter know that?

_It's impossible._

Did he… did he have access to Leo's memories?

_I don't remember what happened between the moment I finished the mantra and the moment I landed in Mikey's mind, except for the pain._

Raph raised his fist to bump it against Leonardo's, and Leonardo reciprocated.

Leo began to panic. Surely they weren't buying it?

Mikey had every reason to be suspicious. Donnie was a genius. Raph was his favorite partner in crime. They were going to notice something. They had to.

But the being moved like him. He smiled like him. He talked like him.

_Don't buy it. Don't buy it! Mikey, please. Remember yesterday. You said it wasn't like me! Trust your intuition!_

Leonardo finished his breakfast and stood up.

"Let's go, guys! We don't want Sensei to wait for us."

"Sure we don't." Donnie grimaced.

As the three of them stood up to follow him outside the kitchen, Leonardo turned to Mikey and patted his bald head.

"I'm sorry about yesterday, Mikey."

Mikey beamed, his hurt already forgotten.

"No problem, bro," he answered.

Trapped inside his brother's mind, Leo screamed.


	4. Training Session

**Notes for the Chapter:**

> _Leo refers to Leo. Leonardo refers to the not-Leo being._

It was worse than he had thought.

Leo realized that he had kept hoping his father would notice something - Splinter was the most spiritually refined of them all, and he knew them by heart, how could he not?

But the rat master hadn't twitched a whisker when his four sons - well, his three sons and the imposter - had knelt in front of him at the beginning of the lesson.

Leo wondered, not for the first time, how powerful the being that had taken over his body was. Could he somehow reproduce Leo's aura, to the point even Master Splinter would be fooled? If it was the case, Leo was in a dire situation indeed.

Well, if nobody in his family was going to notice something was wrong on their own, he would have to make them realize it. And Mikey was his best chance - he was in his mind, after all.

 _Mikey,_ he tried once again. _Mikey, please, listen to me. I know it sounds weird, but I'm inside your head. Brother, you have to help me. Mikey!_

But Mikey didn't react. Leo forced himself to calm down. _Wait and see,_ he thought. _Maybe an opportunity will present itself._

He decided to pay close attention to Splinter's lesson. When he would have his body back - because he was going to have his body back, he was - he didn't want to fall behind the others.

His father was explaining a new ninjitsu move. Alas, Leo was dependent on Mikey to watch the display, and his brother had apparently decided that it was the right time to look at the wall instead of paying attention to what their father was demonstrating. So Leo was left wondering what the shell "Move your arm like this" and "Don't forget to balance your leg that way" could mean.

 _Mikey, please look at Sensei,_ he grumbled without much hope to be heard.

"Michelangelo!"

Mikey jumped and turned his head, and suddenly Leo found himself staring into the brown eyes of his father. He wasn't prepared for the emotion that filled his being - or what was left of his being - at the sight. He wanted to run to the rat and hug him for dear life, to feel the fabric of his robe against his fingers and arms, to breathe the rodent's scent, to bury his head close to his heart…

 _Sensei._ _It's me, it's Leo. Acknowledge me, please. Please!_

Splinter was frowning, but not at him - at Mikey. He didn't see Leo, he didn't hear him.

 _Father._ Leo felt crushed. He wished nothing more than to close his eyes and breathe deeply, in a poor attempt at finding his balance again, but he was denied even that.

"Michelangelo, why don't you try that move by yourself?" Splinter asked, his exasperation only slightly showing. "You must already have grasped its subtleties, if you think you don't need to listen."

Mikey gulped and Leo pushed his grief aside to focus on what was happening in the dojo. Raph, Donnie and… Leonardo… were looking at him with more or less compassionate expressions. Mikey stood up bravely and waved his arms back and forth, obviously at a loss.

Splinter sighed.

"You'll practice this move two by two. Raphael and Donatello, you're together. Leonardo, you'll help Michelangelo."

From his gentle voice and the fact he wasn't telling Mikey off, Leo suspected that his brother had been using his famous puppy-dog eyes. _Nice move, Mikey,_ he thought in spite of himself.

Leonardo came closer and smiled.

"Look at me, Mikey, and do exactly what I do."

Leo bristled at the voice - his own voice. With a heavy heart, he watched himself demonstrate ninjitsu moves to his brother - slowly, carefully and with deadly grace, although Leonardo had only learned the moves minutes ago.

It was a sickening display. It had taken Leo years and years of hard work to achieve this level of skill, and now he could only witness this _thing_ boast in his body as if it was easy.

His only solace was that Mikey focused hard on Leonardo, and so he could finally learn the sequence.

When Leonardo was done, Mikey looked at his two other brothers, and Leo had the opportunity to witness Raph's deadpan expression - as if he was torn between admiration and the will to smack Leonardo.

 _Please, be my guest and choose the second option,_ Leo thought wryly. _You have my blessing._

"Very good, Leonardo," Splinter praised, and for the first time in his life Leo didn't enjoy these words.

Leonardo bowed.

"Your turn, Mikey," he said kindly.

Mikey nodded and tried to replicate the moves. Every now and then Leonardo would correct him - although Leo quickly realized that he wasn't being helpful. He would criticize Mikey when he was doing the moves right, and not say anything when he was wrong - unless Splinter was looking at them.

Which meant it was deliberate.

The thought was infuriating Leo. How dare that thing mislead his brother? Didn't he care about him at all?

 _No,_ Leo realized with sudden dread, _of course he doesn't. He's just playing with him._

Like a cat with his prey.

Confused by Leonardo's directions, Mikey finally lost his balance and fell on the dojo floor.

"Almost," Leonardo said, and although it was impossible to catch if you weren't looking for it, Leo knew for a fact he had enjoyed Mikey's fall. "Try again."

"Yes, Leo," Mikey said obediently, convinced that he had failed to follow his brother's instructions despite the fact he was being so nice and patient with him - Leo could feel his emotions again and suddenly, it was too much.

He was sick of this, sick of being unable to communicate with his family, sick of being forced to watch this imposter play with his brother's feelings.

 _DON'T CALL HIM THAT!_ he shouted. _IT'S NOT ME! IT'S NOT ME! IT'S. NOT. ME!_

"Ow, Leo, no need to shout, I'm sorry," Mikey said, and Leo froze.

Had his brother actually heard him? A tiny speck of hope lighted up in his mind, and then -

"I didn't shout, Mikey," Leonardo said, his tone suspicious.

Mikey blinked.

"Uh, I thought… I thought I heard you… In my head…"

"That's ridiculous." Leonardo was watching him, or watching _through_ him, and Leo realized with horror that the imposter knew he was there. He made himself as small, as insignificant as he could. _Stupid, stupid,_ he chastised himself. _Couldn't you just have shut up?_

"Your imagination is way too wild, Mikey," Raph said, shaking his head. Next to him, Donnie smiled indulgently.

"Yeah, I know." Mikey's tone was cheerful. Leo could picture him grinning. "But I like the idea, dude! I would be the first mutant ninja telepath in the world!"

Leonardo's mouth curved upwards, but the smile didn't reach his eyes. To Leo, these eyes seemed cold and calculating, although nobody else seemed to notice.

He didn't dare to say anything else for the rest of the training session, waiting impatiently to be alone with Mikey - he had managed to communicate with him once, surely he could do it twice, talk to his brother, convince him that he wasn't dreaming, and more importantly, warn him against Leonardo - but when Splinter finally dismissed his sons, Leonardo stayed close to Mikey. Way, way too close for Leo's liking.

"Hey Leo, are we going to patrol tonight?" Raph was playing with his sai, already anticipating a good outing with his brothers.

 _No,_ Leo thought desperately, wishing that Raph wouldn't be so enthusiastic. Couldn't he be all grumpy and determined to stay inside the lair, beating his punching ball or watching TV? Or even calling Casey and going outside with him - everything but patrol.

Under any other circumstances, he would have laughed at himself for thinking that - but he was too busy worrying, and the irony was lost on him.

"Yes, I could use some fresh air," Donnie agreed.

 _Don't you have an urgent project requiring your full attention? Something to build? Something to destroy?_ Leo pleaded, in vain.

Because Leonardo was already nodding.

"Yes," he said, his eyes never leaving Mikey. "Yes, we're going on patrol tonight."


	5. Patrol

Leo felt his anxiety grow and grow as the minutes passed. Leonardo hadn't tried anything so far - he was just leading _Leo's_ three brothers across the rooftops of New York. At high speed.

 _I hope you're enjoying my body,_ Leo thought bitterly.

He hadn't dared to reach for Mikey again. He didn't want to take the risk to attract Leonardo's attention on him. Mikey was bantering with Raph as if he had no care in the world, which was probably the case. He must really be convinced that his wild imagination was messing with him.

Leo was trying to keep his focus on Leonardo, but Mikey was making things difficult for him. He was looking everywhere but on the leader he was supposed to follow, and only vaguely looked at the ground he was running on or the buildings he jumped towards.

You really wondered how he _still_ managed to keep pace with the others. While it drove Leo crazy, it also impressed him.

"Oh, guys!" Donnie suddenly stopped, pointing at something in the alleyway below. "Look at this beautiful central processing unit! Why would anyone _throw_ that?"

"Maybe because it's broken?" Raph suggested.

Donnie shook his head. "Then people should repair it."

"If they didn't, you would have nothing to play with," Mikey added.

Donnie smiled at him.

"A fair point, my dear brother. I say this unit will be _mine_."

"Donnie, a training run isn't supposed to be interrupted by dumpster diving." Leonardo's opposition didn't seem very strong, though, and Donnie didn't fail to notice it.

"Oh come on, Leo, it will save me hours of work! Please, it'll only take me a minute to retrieve it!" he pleaded.

Leonardo let out a long-suffering sigh.

"Alright, do it. Raph, can you go with him and keep watch?"

Raph nodded. "But I'm not carrying anything this time."

"Of course not, of course not." Donnie rubbed his hands. "See you in sixty seconds, guys!"

He began running towards the dumpster below, Raph following him close.

Which meant that Leonardo was now alone with Mikey.

 _Only for one minute,_ Leo thought. It was probably a good thing that he had no heart at the moment. This way, a cardiac arrest was impossible. _What's the worst that can happen in one minute? Fifty-nine seconds. Fifty-eight seconds…_

Leonardo wasn't even paying attention to Mikey. He was looking at an oddly-shaped air vent.

"Can you imagine how amazing it would be if someone could jump from that air vent and land on the next rooftop?" he whispered to Mikey. "Without hitting all these satellite dishes, or the clotheslines, of course. Only the best of ninja would undertake such a feat."

Leonardo smiled - a false smile if you asked Leo, but Mikey didn't seem to notice.

"Maybe one day we will be able to, who knows?" Leonardo added dreamily, patting the air vent before walking away.

Leo could almost physically feel the idea taking shape in Mikey's mind - and of course that was what Leonardo had hoped for.

He was going to try it. He was going to show his brother how amazing he could be…

For the first time since his disastrous attempt in the dojo, Leo tried to speak to his brother.

 _Mikey, don't. It's a very bad idea and you know it,_ he whispered.

For a few seconds, it almost looked like Mikey's subconscious was listening. He turned away from the air vent and began following Leonardo - and for once Leo didn't complain.

Then, as if on second thought, he turned around and jumped on the air vent, intending to launch himself in the air and avoid the obstacles with almost impossible moves.

And to Mikey's credit, his agility and flexibility were amazing. He might have managed to do so, if his foot hadn't met a substance that wasn't supposed to be on an air vent, a substance that looked like…

 _Grease?_ Leo wondered in horror.

Mikey's foot slid, altering his balance and sending him right into the forest of satellite dishes, then on the clotheslines, and then - plunging to the alleyway below.

* * *

Mikey was shouting so loud that Leo couldn't hear anything else as the ground came closer and closer. He expected to crash any second, then suddenly he was viewing the sky again - and he realized that Mikey had used his kusarigama to slow down his fall and redirect it to an open dumpster.

_Way…way to go, Mikey._

"Ouch," he heard his brother moan.

"MIKEY!"

Raph and Donnie, alerted by the noise, were bursting out of the nearby alleyway. They weren't carrying anything - Leo assumed that they had dropped everything in their haste. Leonardo was already there, and he managed not to look too disappointed - that stinking traitor.

"I'm sorry, guys," Mikey said miserably. "I slipped."

"Mikey, can you feel this?" Donnie said, poking and prodding Mikey's limbs and making sure he had nothing broken.

"Ouch, ow, ouch," Mikey answered. "Yes I can, Donnie!"

Donnie let him go with an apologizing smile. Raph shook his head, his tone gruff. "You should be more careful, Mikey."

"Is he alright, Donnie?" Leonardo asked.

It infuriated Leo that his tone sounded so sincerely worried.

Donnie nodded. "You've been lucky, Mikey," he scolded, patting the top of Mikey's head.

 _Lucky?_ Leo could think of a few other words better suited to the situation, but there was no way Donnie would have thought otherwise.

Neither him nor Raph would ever suspect Leonardo, not in a million years. He was the leader in blue who did everything it took to get them through, no matter the cost to him. It was unthinkable that he would deliberately try to harm one of his own.

Leonardo put an arm on Mikey's shoulder.

"Maybe we should go back to the lair. Where is your unit, Donnie?"

"Just around the corner," Donnie answered. "Along with, hum… a few other things I thought could be useful. Raph?"

Raph watched his purple-clad brother with narrowed eyes. "I told you I wasn't going to carry anything."

"If you do, I'll build you an exercise machine like no one has ever seen," Donnie negotiated.

Raph seemed to hesitate, maybe wondering if it was a good thing or not.

"You won't make it sentient?" he inquired.

Donnie grinned. "Of course not, why would I do that?" Ignoring Raph's shrug, he went on. "So, do we have a deal?"

Raph nodded, still looking a bit suspicious, and both he and Donnie began heading towards the alleyway. To Leo's deepest relief, Mikey followed them.

* * *

On the way home, both Donnie and Raph were carrying heavy bags. Raph was complaining that it was the _last time_ he carried anything for Donnie, while Donnie replied with _of course, of course_ and _how many weights do you want for your exercise machine?_ and Leo might have enjoyed their banter more if Leonardo hadn't been running next to Mikey.

 _He won't try anything, not when Raph and Donnie are so close_ , he tried to convince himself.

However, when they ran across a particularly damaged rooftop with brick chimneys threatening to collapse, and Leonardo suddenly disappeared, Leo didn't need his prodigious intuition to know that something was about to go very, very wrong.

Mikey wasn't looking at the chimneys, so all Leo could do was to listen with his ears… To listen very carefully until…

 _GET DOWN!_ Leo shouted, not caring if Leonardo could hear him. It was a desperate shout, even more so than it had been during training, and Mikey was going to hear it, he had to…

Mikey reacted on instinct and a brick avoided his head by mere inches.

"Leo?" he asked, incredulous.

 _Mikey,_ Leo thought desperately. _Mikey, hush. I'm in your head. Don't say anything aloud!_

 _Leo?_ Mikey asked again, this time in his head. _Leo, is that you?_

 _Yes, it's me._ Leo felt joy mix with his frantic worry. Finally, finally, his brother was listening to him!

 _What are you doing in my head?_ Mikey sounded more curious than offended.

Leo tried to think of a good explanation for that - one that wouldn't scare his brother - but he was running out of time.

 _Somebody took over my body,_ he answered, feeling almost as stupid as he was desperate. What would he do if Mikey didn't believe him? What would he do if his brother blamed his wild imagination again? What…

 _Okay,_ Mikey answered, as if it was the most natural thing in the world. _Don't worry, bro, we'll find a solution. In the meantime, you're welcome! Make yourself at home!_

Leo didn't know if he was more moved by Mikey's calm acceptance of the truth or by his generous offer. _You..You're trusting me? Just like that?_

 _Yes, of course, Leo! It's exactly like in that comic I've been reading, where the main character has to share his body with his best friend! Have I already told you how_ awesome _that story was?_

 _ON YOUR LEFT!_ Leo shouted again, and Mikey jumped to avoid another brick. Raph and Donnie were still chatting, blissfully unaware of the drama behind them.

 _Ow, Leo, stop shouting,_ Mikey complained. _I'm hearing you just fine!_

_Sorry. Listen, Mikey, I don't know who did that to me, but he's after you. You can't trust that thing!_

_By that thing, you mean you?_ Mikey inquired.

_Yes. No. You see what I mean._

_I hear you loud and clear,_ Mikey answered happily. _I can't trust you, I can only trust you. What do we do?_

_I… Forget it. You need to stay very close to Donnie and Raph. I don't know why, but this thing-that-isn't-me seems to prefer discretion._

_No problem, bro, I have the perfect plan. Trust me!_ For someone who was the target of a maniac having taken his brother's body, Mikey sounded really enthusiastic.

Leo couldn't have done anything else anyways, and he watched as Mikey ran to Raph.

"I'm hurting," his brother began. "I'm huuuuuuuurting. Raph, I can't walk anymore!"

Raph gave him a concerned look, trying to decide whether or not he was serious.

"They should have left a warning sign or something," Mikey went on. "Slippery rooftops are dangerous! Now my body will ache for days! For months, even! I'm going to sue them!"

"Sue…who?" Donnie asked, more out of habit than because he really wanted to hear the answer.

"The humans, of course! What about teenage mutant ninja turtles' protection and welfare, I'm asking you?"

"Alright, Mikey lost it. Again." Raph shook his head.

Said Mikey began limping.

"Raph," he moaned. "Raaaaaph. Raaaaaaaaaaph!"

Raph put his hands on his ears.

"I'm not listening to you."

Mikey jumped right in front of him and fell to his knees.

"I'm a poor hurt turtle," he begged. "You must help me!"

Raph was spared an answer by Leonardo's reappearance. The blue-clad turtle didn't look happy.

"What's the matter, Leo?" Donnie asked.

"The chimneys are threatening to collapse," he said. "It's dangerous, we should hurry."

Leo refrained from thinking too loud what he wanted to call the imposter. Now that Mikey was paying attention to him, he had to watch his language.

"I can't hurry," Mikey whined. "I can't, because my legs are hurting, and my feet are hurting, and my toes are hurting, and…"

"Technically, it is possible that he would only begin to feel his injuries," Donnie said in a worried tone. "The adrenaline must have worn off."

Raph glared at him, then at Mikey, then at Leonardo, then at the sky. With a sigh, he moved the bag he was carrying and motioned for Mikey to jump on his shell. Mikey happily did so and put his arms around his neck, giving Leo a close-up view on Raph's plastron.

With embarrassment and a tiny bit of nostalgia, Leo realized that it had been a very long time since he had last ridden on his brother's back. He shrugged the thought off.

 _Well done, Mikey,_ he whispered.

_Told you. I'm a pro. What's next, Leo?_

_We… You wait until_ he _goes to bed, you tell Donnie and Raph, I take my body back._

 _Sounds like a plan,_ Mikey approved.

He didn't tell that it was a very vague plan, which Leo was grateful for. He could always precise it later. For now, he was happy enough to be able to communicate with his brother.

He merely hoped that his other brothers would believe Mikey.


	6. Of Course, Mikey

**Notes for the Chapter:**

> _Thank you so much for your reviews! I love them all. :D_

Leo kept watching Leonardo's slightest moves during the way home, but the imposter didn't try anything else. Maybe three murders attempts were enough for one night, or maybe he really didn't want witnesses. Leo wondered with a shiver if he didn't attack Donnie and Raph because he had nothing against them or if he restrained himself for fear of losing. He had to be limited by Leo's abilities, and Leo wanted to believe that his body wasn't going to give his full potential in a fight against his very own brothers.

The mere thought that his training and talent could be used against his beloved family made him sick.

_Leo, is everything alright?_

_Mikey_ , Leo answered, chastising himself for letting his worry reach his brother. He had to guard his thoughts better than that. _Yes. I was just thinking aloud - or not aloud. This situation isn't easy to deal with, although I'm grateful for your… hospitality._

 _You got that right. I'm here now, everything is going to be fine._ _Do you want me to imagine something for you?_ Mikey suggested, eager to distract him. _I personally enjoy unicorns these days, but maybe you would rather live a high-speed space chase?_

Leo was lost at the first part of his brother's offer.

_Imagine something for me? What do you mean?_

Mikey didn't answer, but a few seconds later, Leo found himself riding a unicorn amongst the stars next to Captain's Ryan space shift.

_WHAT THE!_

The scene immediately disappeared to be replaced by the familiar sight of rooftops and mutant turtles.

 _You don't like it?_ Mikey asked sadly.

Leo gathered his thoughts.

 _No, Mikey, it was great_. _I just wasn't expecting it_. Feeling that his brother was ready to bring him back to space, he hurriedly went on. _Although maybe_ _it would be better if we focused on the situation at hand, you know?_

 _I can do both_ , Mikey claimed proudly. _I'm doing it all the time!_

 _All the time?_ Leo answered weakly. _You're imagining yourself in situations like this all the time?_

_All the time._

_Even during patrols?_ Leo didn't really want to know, but he had to ask. It was important input for the leader he had become.

_Of course, bro! That's the perfect atmosphere!_

If Leo could have had his body back at this precise moment, his first action would have been to rub his aching temples.

_Mikey..._

_Yes, Leo?_

_When on patrol, you're supposed to focus on…patrol._

_You mean you never picture a completely different world in your head?_

_No._

_Never ever?_ Mikey sounded disappointed, and Leo felt the need to defend his own imagination.

_Well, sometimes I do, but not during patrols._

_Oh. Okay._

Leo could tell that his brother didn't really understand, but didn't want to upset him. _Focus is important,_ he grumbled, more to himself than to Mikey.

They were almost at the lair, and it didn't last long until they finally jumped the turnstiles leading into their home.

Raph immediately deposited Mikey on the sofa, dropped his bag at Donnie's feet and stretched with a sigh.

"Last. Time," he said.

"My sons? Why are you back so soon?"

Mikey turned around and Leo saw Splinter hurrying to them.

"Mikey fell," Leonardo explained.

Mikey nodded proudly. Frowning, Splinter briefly checked him up. Apparently satisfied by his examination, he smiled.

"What happened, my son?"

Mikey shrugged.

"I slipped. Humans don't clean their rooftops properly up."

 _Humans had nothing to do with it,_ Leo stated, as if his father could have heard him.

"Hmm," Splinter answered, stroking his beard.

Maybe he was surprised that Mikey would protest about insufficient cleaning. The turtle had no problem avoiding random items and pizza grease on the floor as far as his room was concerned.

"Leonardo, may I speak with you?" Splinter tilted his head towards said son, who reluctantly nodded.

"Of course, Sensei."

 _Yes, go_ , Leo thought.

It couldn't have been a better opportunity. He wasn't worrying about the imposter staying alone with his father - Splinter could take care of himself - and Mikey would be able to talk to their brothers privately.

As soon as Leonardo and Splinter had left, Mikey turned to Raph and Donnie.

"Guys, I have something important to tell you," he whispered urgently. "It's about Leo."

Both turtles looked at him with perplexity.

"About Leo?" Raph repeated. "What would you want to say that he can't hear?" His face brightened. "Do you want to prank him? I'm warning you, my silence will be more expensive this time."

 _This time?_ Leo's suspicious thought was met with guilty silence from Mikey's part.

"We're listening, Mikey," Donnie said indulgently, unaware of the fact he was distracting Leo's attention - to Mikey's utter relief. "What is it about?"

Mikey took a deep breath and Leo tensed. It was the moment of truth.

"He's in my head." Mikey's tone couldn't have been more serious, but Donnie and Raph looked dubious at the very least.

"In your head." Donnie sighed. "Mikey, I don't know how to tell you this, but Leo can't be in your head. People can't be in each other's heads. Leo is in the dojo, with Master Splinter."

"Like brains couldn't be in chests?" Mikey exclaimed, a little angry at the patronizing tone. "Guys, you have to believe me!"

 _Yes, you have to!_ Leo approved.

"And…" Donnie began, pinching his forehead, "how is it possible that he's still talking and walking?"

Next to him, Raph just shook his head indulgently.

 _That's because something took over my body,_ Leo thought.

"That's because something took over his body!" Mikey translated.

"Of course, of course." Raph yawned. If anything, he looked bored. "I'll be in my room if anybody needs me."

Leo wanted to ask him to stay, and Mikey jumped on Raph's way, but the red-clad turtle just grabbed him by the shoulders and put him aside.

 _At least, tell him to stay away from… the me who isn't me!_ Leo said desperately.

"Raph, at least stay away from Leo who's not Leo!" Mikey exclaimed.

"Sure." Raph rolled his eyes. "I'm going to avoid my brother because he's in your head. Go take a nap, Mikey."

"No, Raph!"

But Raph was already gone, and Mikey reported his attention on Donnie.

"Donnie, I'm telling the truth!" he pleaded.

_Yes he is, Donnie!_

"You're saying that something took over his body." Donnie chuckled. "And who would that be, hmm?"

"A… a…" Mikey stopped.

 _Leo?_ he asked.

_I don't know! A spirit? A demon? I don't know!_

"He doesn't know," Mikey reported dutifully.

Donnie raised an eye ridge.

"He?"

"Leo! I told you, he's in my head!"

"Of course, of course." Donnie put a soothing hand on Mikey's shoulder. "Raph is right, Mikey. Go take a nap. You'll see, you'll feel better afterwards."

"You don't believe me, do you?" Mikey protested. "You're not even listening!"

 _I have to admit, it's hard to believe,_ Leo thought sadly.

 _It's more than that,_ Mikey refuted. _You never take me seriously!_

He was hurt, really hurt, and Leo had a nasty feeling that his brother was right.

 _I'm sorry, Mikey_. _Don't give up. There has to be a way to convince them!_

"Mikey?"

Mikey turned around. Leonardo was standing in the dojo entrance.

"Master Splinter wants to talk to you," he said softly. "About what happened tonight."

Leo could feel his brother's hesitation.

_Leo, what do I do?_

_You will be safe if Sensei is there,_ Leo reasoned. _Go._

Nodding, Mikey followed Leonardo inside the dojo. Splinter was waiting for them, his hands crossed on top of his cane.

"Michelangelo," he began sternly. "Leonardo told me what happened."

 _I don't think so._ Leo was expecting the worst.

"Your lack of focus has endangered you once again. My son, you need to pay more attention to your surroundings."

"I'm getting better!" Mikey protested, heartbroken, as if he was truly at fault.

At Splinter's side, Leonardo let out a long-suffering sigh and exchanged a meaningful glance with Splinter.

 _It wasn't you, Mikey,_ Leo thought fiercely. Leonardo's acting was sickening him. _He tricked you into jumping from that air vent!_

 _He did?_ Mikey sounded surprised.

_Yes. Yes he did._

"Your brother is willing to give you private lessons to help you with that. He has my blessing," Splinter went on.

 _NO!_ Leo shouted.

"No!" Mikey protested, way more weakly.

Leo could feel that he wasn't entirely opposed to the idea. Actually, he would have liked it very, very much if it had truly been Leo offering his help. Spending time one-to-one with his brother was fun, and it had become rarer and rarer.

 _Mikey?_ Leo whispered.

Mikey must have realized that he was sharing his feelings with him, because he abruptly hid them.

"Don't worry, Mikey, we'll go at your own pace," Leonardo offered with a smile. "I only want to help you."

 _No_ , Leo thought again. He wanted to ask Mikey to tell Splinter the truth, right here, right now, but would his father believe it or would it make matters worse? He didn't know how Mikey would take another rebuff, or what the imposter might attempt.

_No. No. No._

He felt defeated.


	7. Another Try

Helplessness.

It was filling Leo's consciousness with the dark, cold certainty that there was nothing he could do to escape his fate. His time on this Earth was at an end. He had already lost his body, soon he would also lose his last ties to the world of the living.

It was bound to happen…

 _No_.

Why fight? Why not let go, right here, right now? Mikey would be sad, maybe, but the others would never know. They would still have a Leonardo.

_No! I won't give up!_

This was hopeless. Hopeless. Why not spare himself the pain? It would be so easy. He just had to give up…

_NEVER!_

_Leo?_

Mikey's thought seemed to come from far, far away, but it was enough to return Leo to reality. His brother - and thus, himself - was looking at Leonardo, at his soft, gentle smile that suddenly froze, and Leo realized that whoever was inside his body had tried to influence him.

 _I will never let you harm them,_ he whispered, giving the words all the strength he could. _You won't win. I'm not giving up._

 _Leo!_ Mikey called again, his tone a little more desperate, and Leo turned his focus on him.

 _I'm here, Mikey,_ he answered fiercely. _We'll find a solution._

They needed a plan so Mikey wouldn't have to attend private lessons with somebody who had already tried to kill him. Who was the most susceptible to help them? Who would believe Mikey's crazy tale?

 _Ice Cream Kitty would,_ Mikey offered helpfully.

Leo tensed. Apparently, he was becoming less careful in guarding his thoughts, or maybe Mikey was becoming better at picking them up.

 _Uh… That's a start,_ he answered with diplomacy.

Leonardo was still watching Mikey with a gentle expression. That _thing_ was way too good at acting to Leo's taste. He wanted nothing more than to punch him in the face to make it stop. _I wonder if it would count as self-harm._

"Michelangelo," Splinter called, and Mikey turned his head to look at their father.

The ninja master came closer and put a hand on Mikey's shoulder. Leo felt his brother relax and wished he could share his sense of touch.

"My son, I trust you to do your best. I need you to be able to take care of yourself, no matter the circumstances."

 _If only you knew about these circumstances,_ Leo sighed.

 _Maybe we should tell him?_ Michelangelo suggested. _I could say that I want to talk to him in private._

 _But then_ he _would stay alone with Donnie and Raph, and they have no clue what's happening._ Leo's mind was already picturing Leonardo sneaking inside Donnie's lab or Raph's room, using his stealth to approach them with his katana in hand, while Leo and Mikey would be trying to convince their father that they had become one being.

Granted, the imposter hadn't tried to harm Raph and Donnie so far, but that didn't mean he wasn't going to. Who knew what agenda he had?

Behind Splinter, Leonardo had narrowed his eyes in a threatening expression.

"You will begin your lessons tomorrow," Splinter went on. "I want you to rest tonight."

Mikey nodded. As he headed for the exit, Leonardo followed him like an ominous shadow. Leo was wondering if he would stay with them for the rest of the night - well, at least that way he could ask Mikey not to lose sight of him - when Splinter called him back.

"Leonardo. Have you forgotten your own private lesson?" their father asked, clearly amused.

 _Oh, right! I did forget,_ Leo thought. He was supposed to learn how to properly use the healing hands technique with his father and Sensei.

And to think that it was how it had all begun.

 _How?_ Mikey asked. _You never told me._

Leo felt that he owed him the truth, and he forced himself to answer.

 _Well, I mi-might have tried a new scroll without... without... well, you know, telling Sensei... about it?_ He wanted to disappear inside a tiny, tiny hole as he waited for his brother's reaction.

 _Dude, did you invoke that thing or something?_ Mikey sounded more impressed than disapproving, to the point Leo considered asking him to tell him off.

 _Nah_ , Mikey answered, showing Leo once again that he had to do a better job thinking to himself and not to his host. _Raph will do it wayyyy better than me._

_Well, that's comforting, thank you._

_You're welcome, bro._

Next to them, Leonardo seemed hesitant.

"Maybe we could report it? After tonight's events, Mikey..."

 _He's going to use you as an excuse,_ Leo quickly whispered to Mikey. _Don't let him do that_. _It's our opportunity to try our hand again at convincing the others!_

_Got it._

"Aww, don't worry about me," Mikey said enthusiastically. "You just told me how important these lessons are to you!"

Obviously, Leonardo wasn't the only one gifted at acting. He glared at Mikey, but he couldn't slip away now without making Splinter suspicious.

_Now let's go back to Raph and Donnie. We have maybe one hour to convince them._

_Do you think it will be enough?_ Mikey sounded dubious.

Leo couldn't blame him after the way they had dismissed his story. He did his best to hide his own doubts. He would trust his brothers.

_Of course! I have a plan._

* * *

A few minutes later, Mikey pushed Donnie's door and perked inside. Donnie was turning his back to him, lost in the contemplation of a blank flip chart.

 _Target in sight,_ he said to Leo. _It looks like he's out of inspiration._

 _Perfect_. _He'll welcome the diversion._ Leo did his best to make his thoughts as self-confident as he could. They had to convince Donnie. _It's up to you now._

"Uh... Donnie?" Mikey called.

As Donnie didn't answer, he came closer to him and poked his arm.

"Dooooonnie!"

Donnie jumped, as if he was pulled out of deep thoughts.

"Yes, Mikey?" he answered, his righteous irritation almost not showing. "If it's to talk nonsense again, I'm not available."

Leo felt a little offended that his situation was considered as nonsense by his genius brother. Hopefully they could make him change his mind. Or maybe it was because Mikey was the one involved? Leo couldn't help thinking that Donnie would have been less dismissive if the situation had been reversed and it had been Leo pretending to hear Mikey in his head.

 _Yeah, absolutely,_ Mikey approved. _But he'll listen to me in the end, trust me on that. I'm persistent._

As if to prove his point, he tilted his head and squinted hard at the flip chart.

"Becauuuuse?" he asked.

There was nothing to see but white paper, and Leo wasn't surprised to hear Donnie cough embarrassingly.

"Because I'm busy, what do you think?" he pretended.

"Busy doing what?" Mikey insisted, his tone all innocence.

"Busy thinking." Donnie crossed his arms. "What do you want?"

His tone was less dismissive this time. Obviously, he wanted to change the subject.

 _Okay, phase 1_ , Leo whispered. _Intrigue him._

"I have a question for you, Donnie. Do you remember when April and Casey switched bodies?"

Donnie tilted his head, trying to guess where his brother wanted to go.

"Yes?"

"Then it was Raph's turn. With a Kraang!" Mikey shook his head slowly, as if he still couldn't believe that he had witnessed such a great event. "I was wondering, how is it possible? Scientifically speaking, of course."

"Oh, now you're interested in science?"

Leo could tell that Donnie was torn between curiosity and skepticism.

"Always, bro! I thought you might help me to understand. With you being a genius and all."

 _Are you sure it's not too much?_ Leo asked, a little dubious.

 _Nope. It's never too much_ , Mikey answered proudly. _Besides, you know how Donnie loves to explain._

 _Oh, I do._ Leo sighed.

"Well, Kraang technology was involved," Donnie began. "I assume they used quantum intrication to alter brain cells in a synchronous way..."

"Uh uh, uh uh," Mikey approved.

 _Just to make sure, Leo,_ he added with a little concern. _I'm not the only one who has no clue what that means, right?_

 _Correct._ Despite the situation, Leo would have grinned if he had been able too.

"Raph's case is especially interesting," Donnie was saying. "He adjusted quickly to being a Kraang, while the Kraang couldn't fool us."

 _This is our opportunity_ , Leo whispered. _Phase 2, take the offensive!_

"So you're saying that a spirit can occupy another body than his own, and fool everybody around him?" Mikey cut him off.

"Not everybody," Donnie protested. "Close friends and family would know. Some things are impossible to fake."

"Even if you had access to a person's memories and abilities?"

Donnie began pacing, which was a good sign. It meant that he was taking the conversation at heart and wanted to provide a well-thought answer.

"I guess it would make things harder to notice. But placed in a new situation, one where I couldn't deduce an appropriate behavior from past memories, I would have to make my own choices and probably reveal myself."

 _He's ready,_ Leo whispered. _Phase 3, the final blow._

"And what if _I_ had access to somebody's memories, let's say, Leo's, because, for example, he's with me right now?" Mikey asked, swinging on his heels. "How would you investigate that?"

Donnie tilted his head.

"Well, I guess I would make an experiment. Ask you questions you couldn't answer on your own."

Mikey crossed his arms.

"Go on."

"It's not that I believe your hypothetical situation," Donnie said hesitantly, "but for the love of science… I guess I could give it a try."

 _Finally,_ Leo thought excitedly. _He won't be able to resist good old evidence._

"Go on, Dee."

Donnie straightened up and put his hands behind his back in a teacher's posture.

"What's the sewers water made of?" he asked with a slight smirk.

Mikey shrugged.

"It's water, of course," he answered. "Come on, Donnie, I don't need Leo to know that."

 _It's waste, actually, Mikey,_ Leo said as delicately as he could. _Including, uh, human excrement and so on._

"What? That's disgusting!" Mikey exclaimed, horrified.

Donnie raised an eye ridge, a little puzzled to see Mikey quarrelling with himself. Leo had to admit that it must be weird.

"Another question," he said. "Can you give me ten different ways to infiltrate the Foot headquarters?"

"Of course, bro," Mikey said with certainty.

 _An excellent question,_ Leo whispered. _Well, depending on the setting and the number of people involved, both in the Foot and in the team… Would time be of the essence? Can you spy on them before, do you need a diversion? And…_

As Mikey dutifully repeated Leo's train of thought, Donnie's expression became more and more uneasy.

"This is creepy," he finally said with the greatest calm. "Like, really really creepy. If you're pranking me… I don't know why Leo would get involved in this, but still…"

He moved towards his brother and began searching him, probably for hidden microphones.

"Nope," Mikey answered, allowing the search. "It's not a prank."

Having found nothing, Donnie stopped and took a step back.

"But how?" he muttered, more to himself than to Mikey. "Leo is with Splinter right now."

"Somebody took over his body," Mikey answered. "He messed up with a scroll, or something like that."

Then of course Leo had to give details, and when Mikey was done repeating them Donnie wasn't skeptical anymore.

"Leo, what have you done?" he exclaimed, horrified.

_I know, I know! I'm sorry!_

"So, can you do something?" Mikey asked hopefully.

Leo shared his relief. If they could team up against the imposter, things would soon get back to normal. Leonardo wouldn't be able to watch all three of them. They could devise a plan to communicate with Splinter, use their T-phones to text each other…

"I'll check if I can find mentions of something like this on the Internet," Donnie said, already running to his laptop. "And it would help if you could give me that scroll."

 _It must still be in my room_ , Leo said. _We can check that later. We have to go to Raph first. We don't have much time left._

"See you later, bro," Mikey reported. "We need to talk to Raph now."

Donnie nodded.

"Better you than me," he said solemnly. "I don't think he's going to take it well."

**Notes for the Chapter:**

> _Any reference to the episode _New Girl in Town_ wouldn’t be fortuitous at all._


	8. To Believe or Not to Believe

Mikey pressed his ear against Raph's door and listened intently. Not a sound. Was his brother napping?

He took a deep breath.

"If I don't come back, tell everybody I love them," he said aloud for the sake of using his best drama voice.

 _Come on,_ Leo replied. _You had no second thoughts entering Donnie's lab uninvited, and we both know it's way more dangerous than disturbing Raph._

 _Maybe for you,_ Mikey protested.

With the deep shaky breath of a turtle convicted to death, he pushed the door and tiptoed inside Raph's room. Raph was indeed napping peacefully on his plastron, his mouth wide open.

 _Aww, he's so cute_ , Mikey whispered. _But you wake him up._

 _I don't have a body._ Leo itched to cross his arms. He was regretting his body more than ever.

_That's too bad._

Leo decided that a little encouragement would go a long way.

_Don't worry, it's going to be fine. Just put his sai out of the way._

Raph's weapons lay on the floor, at arm's reach. Mikey tentatively held out a hand and snatched one of them. As Raph didn't react, he outstretched a toe to move the second away. Satisfied, he came closer to Raph, ready to whisper his name in his ear, or maybe shout it - now that he thought of it, maybe Leo should have made sure that it wasn't Mikey's plan - when a green arm closed around Mikey's neck.

Next thing he knew, Leo was watching the floor through Mikey's eyes.

"Ouch!" Mikey protested.

"Mikey, what are you doing here?"

Raph didn't seem particularly happy about his brother's presence. From the direction of his voice and the way Mikey wasn't moving, Leo deduced that he was sitting on Mikey's shell.

_At least he's awake now._

"You said you would be in your room if anyone needed you, and I do."

"And it didn't occur to you that you could knock on the door?"

Mikey gulped. _No. What about you, Leo?_

 _Neither,_ Leo admitted sheepishly. He had been too busy thinking about the upcoming conversation.

Raph knocked on Mikey's shell, his tone clearly threatening. "How many times have I told you to knock on the door, Mikey?"

 _I don't remember, but probably a lot_. Mikey sighed. _Leo, I think this conversation got off on the wrong foot._

_Hmm, maybe try to pretend you did knock on his door?_

_Wouldn't that be a lie?_ Mikey sounded more interested than offended.

 _Well, considering the context and the emergency of our situation… and that we have no time to loose…_ Leo seriously hoped that his thoughts didn't come out as high-pitched as his voice would have.

_It would totally be a lie._

Leo could feel Mikey's happiness at the thought. He sighed. He probably wasn't setting the best of examples for his brother right now.

_It was just a suggestion. If it makes you uncomfortable…_

_No, I'm fine with it._

"I did knock, but you didn't hear me."

Raph considered that for a while. Leo hoped he would let the matter drop.

"Alright. What did you want to tell me?"

Mikey moaned. "It would be easier if you let me go."

Raph hesitated again, but in the end, he stood up and Mikey was able to pick himself up and grab his brother's shoulders to better look him in the eye.

Leo felt uncomfortable meeting Raph's gaze, especially as Raph had no idea he was there. His brother was going to be so mad once they would finally manage to convince him of the truth.

"Raph, I know it's hard to believe, but it is of the utmost importance that you listen very carefully to me," Mikey began in grand style.

Alas, Raph wasn't impressed. "If it's again about Leo being in your head, you can go out right now, Mikey."

"Uh…"

_Leo?_

_Let's try the logical path first. He's not as fond of logic as Donnie, but he won't deny evidence for too long._ At least Leo really hoped so.

"I can prove it," Mikey offered. "Ask me anything you want!"

"Sure," Raph smirked. He smacked the back of Mikey's head. "Did you feel that, Leo?"

"Ouch!"

 _Nope,_ Leo answered. _I can only see and hear._

 _That's so unfair,_ Mikey complained, rubbing his head.

"No, he doesn't," he replied. "He can only see and hear. Another question?"

"Yes." Raph pushed his forehead playfully against Mikey, looking him in the eye again. "Leo, are you in there?"

 _Yes!_ Leo answered lamely. The obvious disbelief in Raph's green eyes was crushing him.

"Yes," Mikey answered, just as lamely.

"Sure." Raph released his brother and shook his head before yawning. "I'm not in the mood for playing, Mikey." He pointed at the door. "Bye!"

 _That's not working, Leo_ , Mikey thought sadly _._

_I can see that. Let me think…_

Leo knew of a situation or two he could remind Raph of, in order to let him know he was truly there. The only problem was that his brother would kill him if he told Mikey about them.

He was pondering his choices - not a single one of them felt fair - when a now familiar voice called from the hallway.

"Raph?"

Mikey froze like a deer caught in the headlights.

"Come in, Leo." Raph smirked. "We were just talking about you."

* * *

Leo was desperate. It was way too early! What had happened? Was Master Splinter alright? Had Leonardo heard their previous conversation?

 _I don't want to criticize or anything, but didn't you say the lesson would last an hour?_ Mikey asked.

_I know! It was supposed to!_

"Really?" Leonardo opened the door and perked inside. "I hope you were speaking well of me, then."

"Well, Mikey was telling the weirdest story," Raph began under Mikey's horrified gaze. "He's thinking that you're…"

"Haha, fun story. I'm so fun!" Mikey launched himself at Raph and glared at him. "The-funniest-turtle-in-the-world!"

Raph gave him a perplexed glance.

"Mikey was telling what?" Leonardo came closer, his expression curious.

"He was telling that…"

"I-was-telling-that-you-were-such-a-great-brother! And-we-should-tell-you-that-more-often!" Mikey laughed like a maniac.

Leonardo's eyes widened a little.

"You're-so-great-Leo," Mikey went on. "Right-Raph?"

Raph looked completely baffled now. It was a good thing that Mikey was known for always doing or saying the unexpected. Maybe Leonardo wouldn't get too suspicious.

 _Right, and pizzas can fly._ Leo sighed.

 _They can._ Mikey's thoughts were adamant.

"I'm… glad you think so," Leonardo said slowly. "Now if you don't mind, I would like to talk to Raph. In private."

"Sure, Leo." Raph nodded.

Leo was pondering if he should ask Mikey to fake a panic attack to distract Raph's attention and prevent him from staying alone with Leonardo - who knew what the imposter would told him, or worse, what he would do to him - when Donnie burst into the room.

"Guys!"

Three turtles turned to him. He leaned against the doorframe, panting.

Raph crossed his arms. "Since when has my room become a meeting place? I thought we agreed that it would never be the case. Did you read what I taped on my door?"

"Yes, keep out and you're not welcome and everything," Donnie answered, waving his hand in dismissal. "Guys, I have great news! I've just convinced Master Splinter…"

Leonardo's eyes narrowed and his fingers twitched. Leo tried hard not to panic.

_Donnie, what are you doing?_

"…to let us have a movie night!" Donnie finished, sliding to allow Master Splinter to enter Raph's room too. "Isn't it great?"

If Leo could have collapsed in relief, he would have. Bless Donnie and his quick thinking. He must have noticed that Leonardo wasn't with Splinter anymore, and anticipated that the he would go to Mikey and Raph.

"Master Splinter?" Raph asked, puzzled.

Splinter nodded.

"Donatello thinks it'll help you release your stress," he said.

"Yes," Donnie went on quickly, looking at Mikey desperately, "because tonight's events have been stressful… with Mikey falling and all that… and that's probably why Le-Leo isn't able to use the healing hands technique right now…" He sent a sheepish glance Leonardo's way. "I, uh, I didn't mean to overhear…"

 _So that's what happened._ Leo couldn't help rejoicing at the thought. Finally an ability that the imposter couldn't use!

Leonardo bowed his head, apparently in shame. Leo suspected that his expression was anything but sheepish - more like plain out threatening. But for whatever reason, he still didn't want to reveal himself.

"A movie night! What an awesome idea!" Mikey shrieked, playing his part to perfection.

* * *

It was the weirdest movie night Leo had ever experienced.

The idea was brilliant - they would watch movies until they fell asleep on the couch, and then Splinter would fondly watch over them. Leonardo would be unable to attempt anything.

Usually, Mikey would have sat on the floor, as close to the screen as possible, but Leo had asked him to keep an eye on everyone, so he was snuggled between Raph and Donnie. He had claimed that place before Leonardo had the chance to sit down. What was more, Donnie was sitting next to Leonardo - Leo had no idea how he managed to look so relaxed - while Raph was at the other end of the couch. Splinter would watch from his favorite armchair. It was the best configuration they could have hoped for.

Neither Mikey nor Donnie or Leo really paid attention to the movie, though. Leo was trying to figure out a way to make Raph understand that something was very, very wrong, and he should begin to listen very, very carefully to what Mikey had to say. This necessity was complicated by the fact Leonardo was close to them.

When cockroaches appeared on screen and Raph tensed slightly at Mikey's side, Leo made up his mind. Between getting killed by Raphael or by the thing that had stolen his body, the first option was still better.

 _Okay, Mikey, listen very carefully_. _But first, promise me you'll never talk about this again after today, alright?_

_Sure, bro. You can trust me._

As Leo finished giving him his instructions, he could feel his brother bristling in anticipation.

 _Dude, why did you never tell me?_ he complained. _With such material, I would have built the best prank ever!_

 _Which is why I never told you,_ Leo answered wryly. _Remember, you've promised._

 _Such a shame._ Mikey shifted so he could rest his head against Raph's shoulder, and by the same occasion have his mouth very, very close to his ear. There was a fair chance that Leonardo would still hear them - Leo had a keen hearing - but he wouldn't be able to pinpoint what Mikey intended to achieve.

"These cockroaches are so gross," Mikey whispered.

As expected, no answer came from Raph - except he tensed a little more.

"I don't know how I would feel if a bunch of them chose my bed as their new home," Mikey went on. "Can you imagine that?"

At that stage, Raph's body was so rigid that he could as well have been a stone statue. As if on cue, the movie gave a close-up view of a particularly disgusting cockroach.

"I would probably run for my life," Mikey added thoughtfully. "To any of you. I would hide under your blankets for the rest of night. And the next morning, I would ask you to get rid of them. I would even," he turned so he could look Raph in the eye, "even go as far as to say _Pretty please._ "

Raph's eyes widened. Mikey released him from his gaze and nudged him.

"But that's only a hypothetical situation, right?"

The next minute was one of the longest of Leo's life. Raph wasn't saying anything, and Mikey was watching the screen. What was happening in Raph's mind? Was he putting the pieces together? Leo sure hoped he would. He felt bad enough revealing to Mikey what was supposed to forever stay between him and his proud, fierce and phobic brother. It better be worth it.

Finally, Raph cleared his throat.

"Hey, Donnie," he said nonchalantly. "Didn't you forget something?"

Donnie gave him a quizzical glance.

"The popcorn," Raph explained. "Come on, bro, you can't have a movie night without popcorn!"

Donnie gaped for a brief second before understanding what his brother had in mind. "You're right! What was I thinking? I'll make it immediately!"

"I'll help you." Raph stood up. "You could get distracted and it wouldn't be as tasty as it's supposed to be."

Mikey and Leo watched their two brothers head for the kitchen. Leonardo didn't try to follow them - he probably didn't consider the preparation of popcorn as an activity threatening his position.

 _Do you think Raph believes me now?_ Mikey asked excitedly.

_I hope so, Mikey. It's a good sign that he wants to talk to Donnie._

Leo listened intently, but it was hard to tell what was being said over the sounds of popping seeds. At least Raph wasn't shouting, so maybe he was taking the news more gracefully than Leo had given him credit for.

A few minutes later, Raph and Donnie came back with a huge bowl of popcorn. Raph's expression had darkened considerably. Leo hoped it was a good sign.

As Raph plopped down heavily on the couch next to Mikey, Donnie offered the bowl to Splinter first.

"Thank you, my son." Splinter took a handful of popcorn and began eating them. "It's delicious."

"Cooperation can do wonders," Raph muttered. "It's so much better than doing things on your own, without asking for help or telling anybody. Which is, you know…" He leaned towards Mikey. "SO STUPID!" he shouted, right in his brother's sensitive ear.

Mikey started.

"Hey!" he protested, rubbing his aching ear.

 _Ouch,_ Leo thought sheepishly. _Sorry, Mikey. I think this one was for me._

 _At least he believes us,_ Mikey soothed him, not resentful at all.

"Raphael," Splinter scolded.

"Sorry, Master Splinter," Raph apologized, although it was obvious to everyone that he wasn't sorry at all. "It had to be said."


	9. Silent Communications

It was already the third movie they watched, and Mikey was beginning to yawn. Leo was under the impression that Leonardo's attention was less focused too - he must be feeling the tiredness of Leo's body.

Next to Mikey, Raph was glaring at the screen as if it was a personal enemy of him, and Leo could feel the anger and anxiety emanating from him. It must be hard for his hotheaded, caring brother to just sit and do nothing when his brother's life was in danger. Leo felt guilty just thinking he was responsible for it.

Master Splinter was watching the movie with a curious expression on his face, oblivious to the ongoing drama, and Donnie… Donnie was tapping his fingers against his thigh, his eyes never leaving the screen.

Mikey - and thus Leo - watched him for a while, as if this was more interesting than the movie itself.

 _Do you think he's calculating the square root of the number pi?_ Mikey asked, and Leo would have gaped if he had been able to. But Mikey was the one who spent the most time with Donnie, so maybe he was more aware of their brother's pastimes.

 _I… I don't know._ Leo didn't think that it was the right time to be doing math, but who was he to judge? _Maybe it calms him down._

 _Maybe,_ Mikey conceded.

Donnie stopped tapping and moved his hand, slowly, deliberately, so it revealed what was behind. Leo immediately felt stupid.

It was Donnie's T-Phone.

And there was only one reason he would have used it for.

 _Check your phone, Mikey,_ Leo said excitedly. _And be careful not to be seen!_

 _On it!_ Slowly, carefully, Mikey took his own T-Phone and glanced at it. He hadn't discarded it after the patrol, nor removed the silent mode - Leo was grateful for that.

 _Uh, Leo? I think Donnie has been at it for a while,_ Mikey said sheepishly.

Seeing what his brother saw, Leo could only approve. Donnie had indeed texted Mikey and Raph - a lot.

\- Guys, we have to talk -

\- GUYS -

\- Seriously, stop watching the movie, it's not even that good -

\- GUUUUUYS -

\- In case you're interested, I told Raph but not Sensei -

\- Didn't have the time -

\- Plus it might not be a good idea -

\- I need to see that scroll -

\- Guys? Anyone here? -

Mikey stopped looking at his phone to watch the screen again and avoid raising Leonardo's suspicions. Leo's mind was spinning. Now that he thought about it, Donnie could have at least tried to warn Master Splinter instead of convincing him to have a movie night. Had he discovered something? Was it dangerous for some reason?

 _We need to answer Donnie,_ Leo said _. Take your time, we don't want _him_ to notice what you're doing, but -_

 _Already done, bro,_ Mikey said proudly, and he glanced at his phone again so Leo could notice that he had, indeed, done so.

\- Got you bro -

 _You… you can text without looking?_ Leo asked, impressed. He hadn't been surprised that Donnie could do it, but learning that Mikey had the same ability was unexpected.

 _Of course._ Mikey's happiness at his brother's surprise was unmistakable.

Raph had apparently noticed their little game, because he discreetly checked his phone too. Then he put it - and his hands - under his legs.

Mikey glanced at the screen of his own T-Phone.

\- djfkhgqqdzqzzle -

 _What do you think he's trying to say?_ Mikey asked, curious.

 _Hmmm…_ Leo answered. Maybe there was a hidden meaning behind his brother's words. And maybe he was just not as gifted as Donnie and Mikey when it came to blind-texting.

Mikey began answering, looking at his phone from time to time so Leo could see what he was writing.

His thoughts were suspiciously mischievous.

\- What's bugging you, Raph?

 _Mikey! You promised me!_ Leo hurriedly protested before his brother could send the text.

 _I promised that I would never talk about it again after today, Leo_ , Mikey replied cheerfully. _We're still today._

Leo couldn't argue against his brother's logic, but he wasn't happy about it. At all. He tried to let Mikey know.

_Dude, are you sure you don't have eyes? Because I could swear that you're glaring at me right now._

_I'll glare way worse if you send that text_ , Leo threatened.

With a discreet sigh, Mikey erased the sentence.

In the meantime, Donnie was getting impatient.

\- Where is the scroll? -

 _It was in my room_ , Leo told Mikey. _Under, uh, my pillow._

 _You put an ancient and precious scroll under your pillow?_ Mikey's question was more curious than critical.

 _I… It was a very tidy pillow,_ Leo defended himself, with more or less conviction.

 _I don't think it's still there,_ Mikey objected.

_Me neither, but it's worth a try._

Mikey nodded and stretched, yawning exaggeratedly.

"I need to go to the bathroom," he said aloud.

"We don't need the details, Mikey," Donnie answered.

"I know, I know. So I won't tell you that it's very urgent and I need to empty my -"

"Mikey!" Raph protested.

Mikey jumped over the couch - Leo was sure he was grinning - and headed for the bathroom. As soon as he was out of sight, he tiptoed inside Leo's room and went straight to the bed - but the scroll was nowhere to be found.

 _I told you so,_ Mikey stated. _Villains aren't that stupid, except when they are, of course, but I had a feeling that this one wasn't - evil spirits are more like, you know, clever and dangerous and plotting evil things and wondering how they could destroy everyth -_

 _Okay, Mikey, I get it,_ Leo cut him off. He really didn't want to hear the details.

He tried to convince himself that it was good news if the scroll had disappeared. It meant that it was somehow dangerous to the imposter.

Now, where was it? There was a possibility that Leonardo would have destroyed it, of course, but Leo refused to give up so easily. Another possibility was that he had hidden it somewhere - and as he possessed Leo's memories, maybe he had used one of Leo's favorite caches.

Which meant he had to tell Mikey about them.

Which also meant he could never use them again.

With a sigh, Leo made his decision.

_Mikey, can you check the wall next to my desk? If you look closely, a part of it can spin and…_

Mikey eagerly did as he was told, and soon revealed a small hole in the wall. To Leo's disappointment, there was no scroll hidden inside of it.

There was, however…

 _Awww, is that a figurine of Captain Ryan? Leo, it's so sweet,_ Mikey teased him.

_Ahem. Now, try the foot of my bed. On the left._

_Dude, it's better than a treasure hunt!_ Mikey happily opened Leo's second cache. There was still no scroll inside. There was, however…

_Hey! It's my candy!_

Right. Leo had completely forgotten that he had rescued it from Mikey's voracity, a week ago.

 _You were too high on sugar,_ Leo said innocently. _It was for your own good._

Mikey ignored him and snatched the sweets, counting them.

 _One, two, three… One of them is missing,_ he accused.

 _I collected a tax for safe-keeping._ Maybe if it was big enough, Mikey would buy it?

Or not. Now it was Leo's turn to feel his brother glaring at him, from mind to mind.

 _Ahem… I think we should go back._ Changing the focus of Mikey's attention usually worked, and indeed…

 _Fine._ Mikey crunched one of the sweets. _But I still need to go to the bathroom._

_Hurry, then._

As Mikey opened the bathroom's door and came closer to the toilet seat, he suddenly had a revelation.

_Uh, Leo? Can you… can you please close your eyes?_

_No. Sorry. I see everything you're looking at, Mikey,_ Leo answered as delicately as he could.

 _Then I'll look at the wall,_ Mikey decided.

Leo grimaced, torn between the relief not to see Mikey pee again and concern for the cleanliness of the room. It was Mikey's decision to make, though, and so Leo watched the bathroom's wall as he listened to his brother relieving himself.

When Mikey was done, he headed for the living room again, reporting to Raph and Donnie on the way.

\- We didn't find the scroll. -

\- That's too bad. -

Donnie didn't elaborate, which was bad indeed if you asked Leo.

\- What's the plan? -

That last text was from Raph. Leo wondered if he had taken that much time to write these few words.

He then realized that they hadn't told the others about Mikey's private lesson, scheduled tomorrow.

_We need to warn them._

Mikey immediately did so, and their brothers' answers came quickly.

\- DJKHSONDCXQW -

\- NO WAY, ARE YOU CRAZY -

 _Tell them they'll follow us and make sure he doesn't harm you,_ Leo said.

Mikey nodded vigorously. _Not harming me, good plan. I approve._

As he came back into the living room and met Leonardo's intense gaze, though, Leo could only hope they would be able to complete said plan.

**Notes for the Chapter:**

> _When possible, the turtles’ texts have been translated in plain English to facilitate reading._


	10. Three Muskeeters

It took half of another movie before Mikey lost his battle against sleep.

And Leo found himself in the dark again.

He had dreaded this moment, but it wouldn't have been fair of him to prevent Mikey from taking a much needed rest. Besides, his father was there, and he would watch over them.

Leo could hear his brothers' breathing, and Splinter's soft footsteps as he stood up and switched off the TV. There was a rustle of cloth and Leo assumed that he had covered them with a blanket. His suspicions were reinforced when he heard his father's voice whisper next to Mikey.

"Sleep well, my sons."

For a second, Leo feared that Splinter was going to leave them - he could feel that the imposter was only faking sleep, his presence a shadow looming over him - but his father sat back in his armchair.

Leo itched to try to contact him - he had managed to go through to Mikey, maybe he could somehow reach his father - but Donnie's warning was too ominous to be ignored.

Why would it be dangerous to tell his father about the recent events?

And, more importantly, had he put his brothers in danger by contacting them?

_Sensei, guys. I'm so sorry._

It was another long night for Leo. He was careful not to let Leonardo influence him, by staying as close as possible to Mikey's asleep consciousness, but he still couldn't help thinking about the recent events. He wanted to talk to Donnie about what his brother had learned. He wanted to reassure Raph that he was alright. And, most importantly, he wanted for Mikey to remain safe.

At some point, Leonardo fell asleep too - as did Master Splinter. Leo waited and waited, but he had no means to know the time, and he was caught by surprise when the night ended.

Leo had half-hoped that Mikey would wake up first, so they could plot behind Leonardo's back, but his brother was still happily snoring. It was a disappointment, but no surprise, when he heard Leonardo stir on the couch.

"Good morning, Leonardo."

Splinter's voice didn't sound tired, and Leo wondered if he had slept at all.

"Good morning, Sensei. Do you want some tea?"

It irritated Leo to the extreme to hear his own voice being so nice and obliging when he wasn't the one to command it.

Not to mention it was awkward.

"Yes, thank you, Leonardo."

Leonardo stood up, and his movements - or the absence of his body on the couch - woke Donnie up. Then it was Raph's turn, and finally - finally - Mikey opened his eyes again.

 _Hi, Leo,_ he said cheerfully. _Today is a great day! It's the day where I'm not going to get killed by the you who isn't you!_

Leo wouldn't have phrased it like that, but hearing his brother ready to fight back renewed his determination.

_And today is the day when I'll take my body back._

He just had to find a way to achieve that without everything going down.

Piece of cake.

* * *

Way too soon for Leo's taste, they were ready to go. Donnie and Raph had tried to convince Master Splinter that they needed special training too, but their father had refused. And so they had to let them leave.

Or more precisely, they had to let Mikey and Leonardo get ahead. Leo took great comfort in the fact that his brothers would be right behind Mikey - or at least as right behind as they could without arousing Leonardo's suspicions.

"Stay safe, my sons," Splinter instructed them before yawning.

"Hai, Sensei," Leonardo answered.

 _We'll do our best, Father,_ Leo promised.

He was expecting Leonardo to change his behavior as soon as they would be out of sight - he knew that Mikey knew, although he might not know that Mikey knew that he knew - but the imposter kept running. And thus, Leo kept worrying.

"So, uh, Leo," Mikey asked. "Where are we going?"

Leonardo gave him an intrigued look, but he didn't answer. He was probably wondering why Mikey still pretended he was his brother.

_Mikey, what are you doing?_

_Conversation. It's boring to just run into the sewers! I should have taken my skateboard!_

_Why don't you check your phone instead? Maybe you have messages._

Indeed, Donnie had been texting them.

\- Guys, you're going towards the broken sewers section! -

Mikey immediately replied.

\- What broken section? -

\- I told you about it three days ago. Ask Leo, he will know. -

_Leo?_

_I don't remember! I must have tuned him out_ , Leo answered sheepishly, feeling like the worst brother of the year. It happened from time to time - when Donnie was on a scientific rant, for example. Leo used to listen carefully when he was talking about security issues in the sewers, though - he felt ashamed that he had missed that important piece of information. Maybe it had been sandwiched between fluid mechanics and quantum physics.

_Ooooh, so you're doing that too._

Nodding, Mikey texted his answer.

\- He doesn't remember. -

The next texts they received were from Raph, who was obviously not blind-texting anymore.

\- The place needs repairs. The city has planned them, but they have been delayed - probably due to their cost. -

\- Also, Donnie swears that next time, he'll make sure you listen. -

\- Just saying, he has his mad scientist face. -

\- No spoilers, Raph. - It was Donnie again.

 _You're in trouble, bro,_ Mikey noted, and Leo could have argued that indeed, he was, and it was hardly breaking news, when -

"Mikey, what are you doing?" Leonardo asked, and Mikey jumped.

"No-nothing!"

Leonardo didn't seem to buy it. He stopped and turned to Mikey. Leo realized that they had arrived in the so-called broken part of the sewers. With its hanging pipes and half-collapsed walls, it looked like the perfect place to make someone - let's say, a teenage mutant ninja turtle - disappear.

Leonardo had a strange gleam in his eyes, and Leo decided to trust his instinct - this wasn't good. Raph and Donnie couldn't be far behind, but they would still need a few minutes to arrive.

 _Okay, Mikey, time to leave_ , he whispered. _You're good at hide and seek, aren't you?_

 _I'm the best._ Mikey might have been exaggerating a little, but he was still excellent - and Leo was counting on it.

_Time to prove that._

* * *

At first, it went well - Mikey could use the many pipes to jump and hide, and his agility was perfect for the place - but Leonardo must have been using other senses than sight or hearing to look for him.

At least, that's what Leo realized now, as Mikey was pinned to the wall by a very threatening Leonardo.

 _Sorry, Leo,_ Mikey said sheepishly.

 _It's really not your fault, Mikey._ The only responsible was himself - and, well, maybe the imposter too.

"What am I going to do with you?" Leonardo whispered. "Maybe I should let you choose. What kind of accident will kill you, what do you think?"

 _I won't let you harm him!_ Leo shouted, even if it was more wishful thinking than anything else at that stage.

"You can't kill me," Mikey replied courageously. "My family will never believe it!"

"I could create a flood. Or make the walls collapse - the whole place is ready to break down."

Leo had trouble accepting that this cold, harsh voice was his own.

"It's nothing personal," the being that wasn't him added. "I just have to get rid of you, you see? As long as you're still there, you retain a connection to your body, no matter how frail."

Which was when Leo realized that he was talking to him.

"You know, spirits usually don't stay that long. You're a rarity."

Leonardo smiled, a cold, harsh smile that didn't belong on his face -

"Stay away from them!"

A furious flash of green collided with Leonardo, pushing him as hard as he could. Leo heard his body hit the wall and inwardly winced. He was, however, touched to have been included in the 'them'.

"Nice timing, Raph." Mikey nodded appreciatively, although Leo could feel him shivering.

Donnie was quick to join them, and he gave Mikey a worried glance, making sure he was okay.

"So you've finally decided to show up." Leonardo stood up, dusting his shell.

"You've lost," Donnie told him. "We know who you are."

Mikey looked at him curiously. From Leonardo's direction, Leo heard a light whistle - a sound he recognized immediately.

It was the sound his katana made when they left their sheaths, and Leo wanted his brothers to hear it.

"Oh great," Raph whispered as he drew his own weapons. "Just what we needed."

* * *

Mikey and Donnie stood frozen as Raph and Leonardo engaged in a fierce fight. At first, it looked as if they were training in the dojo - attacking, counter-attacking and exchanging low blows.

"Don't harm Leo's body!" Donnie instructed, his bo staff at the ready.

Mikey had grabbed his nunchucks, but neither he nor Donnie could interfere. The risk that they would target Raph instead of Leonardo was too high.

"I'm trying!"

Raph sounded a little exasperated. Leo could tell that his brother was trying indeed, but his beloved weapons, his very sharp swords, were not to be underestimated.

Especially not in the hands of someone who mastered them.

Someone who didn't care about not harming his opponent.

Leo could see the moment coming when Leonardo would go lethal - and there was no way he was going to allow that.

 _Tell him he can_ , Leo said grimly to Mikey. _If it's the only way..._ _Tell Raph not to hold back._

He wasn't prepared for Mikey's fierce answer.

 _No way, Leo!_ _There is no way I'll tell him that!_

_Mikey..._

"No!"

Mikey was adamant, and Leo realized that his brother had talked aloud.

"Yeah, forget it, Leo." Raph was panting, but his voice still carried a no-nonsense tone, and Leo wondered if he had somehow guessed the conversation taking place inside Mikey's head.

Leonardo smirked, and Leo tried hard not to panic.

Plan B, he needed a plan B. What had the being said already? ' _As long as you're still there, you retain a connection to your body.'_

Could he somehow find it? Use it? Maybe it wouldn't be enough to take it back, but if he could just weaken it a little…

For the first time, Leo allowed his spirit to wander away from the safe haven of Mikey's mind, trying to enter a trance and maybe, just maybe…

_Yes!_

Leo sent thoughts of tiredness and numbness to his legs and arms, slowing Leonardo's moves.

It was working!

However, the effort it required was huge, and Leo was tiring quickly… He already wasn't sure he could find Mikey back…

But Raph was winning. A little more, just a little more…

 _Leo, what are you doing?_ Mikey's voice sounded panicked.

Leo felt his brother reach for him, anchor him, and suddenly he was with Mikey again and Leonardo was on his knees, Raph's sai restraining him.

Leonardo closed his eyes, and Leo heard him sing in his mind, in a language he didn't know…

"Knock him out!" Donnie shouted.

Before Raph had the time to take the suggestion, though, the wall above them collapsed.

"No!" Mikey launched himself forward and pushed Raph out of the way.

When they stood up again, Leonardo had run away.


	11. Know Your Enemy

_Is he... gone?_ Mikey asked as soon as he had recovered from his shock.

Leo tried to figure out an answer. Now that he knew he was still connected to his body, he could feel it if he focused - and said body was still there, somewhere.

_I don't think so._

_I felt you leave_ , Mikey whispered. _It was scary. Please don't do it again._

Leo coiled his thoughts around Mikey's in the spiritual equivalent of a hug.

 _I'm sorry, Mikey._ He didn't add that he _would_ do it again without a second of hesitation if he deemed it necessary, but his brother must have understood it because he sighed deeply.

Next to Mikey, Raph was inspecting the remnants of the wall in search of his missing sai. He picked them up and put them back in his belt with a frown.

"What the shell just happened?"

Donnie leaned on his bo staff, his expression dreamy.

"I don't know exactly..."

Raph and Mikey both turned to him.

"Then tell us what you think, bro," Mikey encouraged him.

Donnie sighed. "Well, the few stories and rumors I've been able to find describe the existence of mischievous spirits whose only goal is to steal a body and have fun with it. They…" Donnie coughed. "They get rid of the right owner of the body and take his place. They keep a low profile for a few days - maybe to adjust to their new environment. Then they begin to use their own powers, and…" Donnie swallowed hard. "To sum it up, they wreak havoc on the world."

Raph raised an eye ridge.

"Tell me there is something we can do about it."

"Well, making them leave is always… complicated," Donnie answered. "But they remain limited by the body they use - they still have to cater to its needs, to eat and sleep. And they can be banished."

 _How?_ Leo wondered.

"How?" Both Raph and Mikey asked.

"I don't know, guys, I'm no expert," Donnie replied with irritation, although it was more because of his own lack of knowledge than because of his brothers' question. "The stories just say it depends on the way they arrived on this world - so I guess the scroll Leo used in the first place would help us to find answers."

"Why can't we ask Master Splinter?" Mikey tilted his head.

"Because, depending on the spirit… There is a chance he could attack Sensei on the spiritual plane."

"But Splinter is a master," Raph objected.

Donnie threw up his hands. "It makes him more vulnerable. By turning his focus on the spirit, he would allow him to attack, and to… to feed on his energy."

His brothers looked at him, appalled.

"At least that's what I think," Donnie whispered.

At that instant, Leo felt immensely grateful that he had listened to his brother's advice and not tried to contact his father.

"And what about the original spirit?" Mikey asked. "What if he's still there?"

Donnie shook his head. "There is no mention of that."

 _Probably because you can't survive for long without a body,_ Leo mused. He was lucky Mikey had been there that first night to collect him.

 _Sure thing, bro_ , Mikey whispered, as ever receptive to his thoughts. _You're always welcome._

_Thank you, Mikey. I highly appreciate that._

Raph crossed his arms. "Speaking of which…"He turned to Mikey, hands on his hips. "You know, it's really creepy to imagine Leo being in your head. He's probably not going to stay sane for long."

"Hey! For your information, he just said that he highly appreciated me."

"Anyways, I have something to tell him," Raph said, coming closer so he could look Mikey in the eye. "And this is not for you, Mikey, so don't listen." He ignored Mikey's glare as much as Donnie's skeptical expression - after all, if Mikey didn't listen then Leo wouldn't either - and went on. "I've tried to tell you yesterday, but I want to make sure that the message got through."

Raph took a deep breath and on intuition, Mikey covered his ears.

"IT WAS STUPID AND FOOLISH AND DANGEROUS AND WHAT WERE YOU THINKING, LEO?"

 _That it would be helpful_ , Leo grumbled. _You really don't need to rub it in._

 _Oh, I don't know_ , Mikey inserted. _I think he does_.

Donnie tapped his fingers together. "Not that I disagree with you, Raph, but could we please focus on the matter at hand? We need to bring Leo his body back."

 _Yes, please._ Leo was welcoming the change of topic.

"We're not done," Raph whispered, pointing a vengeful finger at Mikey, and thus, Leo. "Where do you think that thing went, Donnie?"

Donnie shrugged. "He could be anywhere."

 _I don't think so. He won't leave too far away as long as I'm still there_ , Leo mused.

The imposter would probably try to get rid of him again. Not that it was a pretty thought, but at least it guaranteed that they would have another chance to stop him.

"I suggest we go back to the lair," Donnie said. "It's useless to stay here, and I would like to do some more research."

"What are we going to tell Splinter?" Raph crossed his arms. "I don't think we'll be able to hide the fact that Leo is missing."

"I don't know, Raph," Donnie answered. "Leo?" he asked, turning to Mikey.

_I'll think about it._

"He'll think about it," Mikey said. "And he also says to carry me, because I'm tired and he can't focus if I'm tired."

_Mikey!_

_What?_ Mikey said innocently.

_What are you doing?_

_I'm lightening the atmosphere, bro._

Raph narrowed his eyes suspiciously. "Is it true?"

Mikey nodded, an angel made turtle.

"I'm unwilling to take the risk," Donnie said, managing to keep his voice level as Mikey winked at him behind Raph's back.

Raph sighed.

* * *

As Raph carried Mikey through the sewers for the second time in two days, Leo tried to decide what the best course of action was. If they went back to the lair, Splinter was going to demand the truth - and he knew none of his brothers could lie to him. If only he could locate Leonardo…

Maybe he could. After all, he was the true owner of that body. He could feel it at the edge of his consciousness. If anyone could figure out where exactly it was, it was him.

_Mikey?_

_Yes?_

_I'm going to try to locate my body. Can you keep a thought on me?_

_Sure thing, bro._

Carefully, Leo focused again on the connection he had felt earlier. He allowed Raph's light footsteps to lull him, falling back into a trance…

There. There it was. Much closer to him than he would have thought. In fact, it was almost as if…

Leo's sudden realization snapped him out of his meditating state.

_He's in the lair!_

_What? But what would he be doing there?_ Mikey asked.

 _I…_ Leo thought about the possibilities. Maybe the imposter needed something that he had left in the lair, like the scroll - but somehow, Leo had a feeling that it was way, way worse than that.

He hadn't even finished formulating his thought that Mikey jumped from a surprised Raph and began racing towards their home.

"He's after Sensei!"


	12. Never Lose Hope

When Mikey, Donnie and Raph arrived at the lair, Splinter was sprawled out on the couch, sleeping peacefully.

With Leonardo bent over him, arms outstretched.

The scroll that Leo and Mikey had been looking for was placed on Splinter's belly, and moved slowly up and down to the rhythm of his breathing. Leonardo was keeping an eye on it. Leo was sure he wasn't reading it, though - the syllables Leonardo was mouthing weren't the familiar words of the healing mantras. Maybe he was using it as a reminder?

But a reminder for what?

"Don't you dare!" Raph shouted, launching himself at Leonardo.

"What did you do to my father?" Donnie noticed the teacup next to Splinter and sniffed it. His eyes narrowed. "You drugged him!"

Leonardo didn't even look at them. With a wave of his hand, he sent them flying over the room, hitting the wall.

 _Wow, he really stepped up his game,_ Mikey commented. Leo could feel his brother's focus and seriousness as he swirled his nunchucks. _What do you think he's doing?_

Leo tried to put the pieces together. What did the imposter want?

Leonardo was watching Splinter's body with unhealthy eagerness, and cold realization dawned on Leo.

Donnie had said that the spirit was limited by the body he used. But what if he could switch? What if he wanted another body, more powerful and experienced than Leo's?

_Oh no._

Leo felt Mikey's horror and knew that his brother had heard his reasoning. He watched, powerless, as Mikey aimed a blow at Leonardo and the imposter avoided it with grace. However, Leonardo didn't counterattack by sending him flying like he had done with the others.

It looked like he couldn't use his powers directly against Mikey - or Leo.

Behind them, Donnie and Raph were standing up with distinct moans.

 _Tell them to stand back,_ Leo whispered urgently.

"Stand back, guys!" Mikey complied.

Raph clasped his sai, torn between listening to an order from Mikey of all people, and not listening to an order from Leo, which usually didn't end well.

"This is weird," he muttered. "This is really, really weird."

Donnie understood immediately. "He doesn't attack Mikey like he attacked us!"

Mikey swirled his nunchucks towards Leonardo, who blocked them again. However, it seemed to convince the imposter that Mikey wouldn't allow him to perform the end of his ritual on Splinter in peace and quiet, because he turned his focus on him and unsheathed Leo's katana.

Mikey gulped.

_This is bad. This is really, really bad._

_Focus, Mikey,_ Leo said. _You can do this._

_Uh, Leo? You're defeating me all the time in training, remember? Of course, there is this time I kicked your butt - but you were a zombie, no thanks to Pizza Face. And that other time when I knocked you out with the Shellraiser's weapons - can I use the Shellraiser again?_

_No time, Mikey._ Leo put all the conviction he could in his words - an exercise that had become easier as he progressed in his leader's journey. _And I'm not myself either this time, right? It's going to work._

_If you say so, bro._

Leonardo moved fast, and Mikey almost failed to dodge the blow in time. Leo heard Donnie and Raph gasp. Splinter, however, was still breathing peacefully.

Mikey jumped to avoid the sharp edge of a sword, and Leo tried to reach his body like he had done before, in the hope of slowing Leonardo down.

 _No, Leo!_ Mikey hold him back, which slowed _him_ down - and Leonardo kicked his plastron, hard.

_Mikey!_

_Ouch! It's okay. It's okay, I'm not hurting._

"That's it," Raph said through gritted teeth, jumping down Leonardo's throat.

At least that was his intent. One split second later, he was colliding with the wall, again.

"Dude, why do you never listen?" Mikey complained as he stood up.

Donnie was trying to sneak his way to Splinter's side, but Leonardo noticed him, and soon he joined Raph against the wall. Then Leonardo turned to Mikey again, his katana ready to strike.

Leo reacted on instinct.

 _On your right!_ he shouted, and Mikey jumped to avoid the blow.

_How did you know?_

_I know how I fight, and I'm all he has got if he can't use his own powers,_ Leo answered. _On your left!_

Once again, Mikey reacted to his thoughts, and soon they were fighting together, Leo disclosing Leonardo's moves just before he made them and Mikey striking, jumping and avoiding.

Leonardo was getting more and more annoyed, and Leo could see the moment when he would make a mistake - and Mikey felt it too, both their minds entangled.

Mikey's nunchucks hit Leonardo's shoulder and sent him tumbling across the room. Leo could feel the stranger spirit's presence, way stronger than before, as he turned his anger towards him, but Mikey struck again, and Leonardo's head hit the wall…

And the spirit was talking to Leo, a raging whispering in his head…

_If I can't have the body I want, you won't either._

Just before Leonardo's eyes rolled upwards, the scroll on Splinter's belly caught fire.

%

"No!" Mikey shouted.

Raph had immediately moved the burning scroll away from Splinter, while Donnie was in the process of tying Leonardo up, although how efficient that would be remained to be proved.

The fire was already dying, the former scroll a pile of ashes.

"What do we do now?" Donnie asked. "We can't let _him_ wake up."

"I'll be happy to knock him down again as often as it will be necessary," Raph growled.

Mikey knelt at Leonardo's side, and hesitantly touched his skin. Leo's connection to his body was stronger than ever, and he itched to just let himself slide inside…

But he couldn't. Something was stopping him - he could get close, yes, and influence its reactions - but taking it back, entirely back, was impossible.

 _It's not working,_ Leo whispered. _Not as long as he's inside my body. We… we need the scroll._

 _Maybe Sensei will remember it,_ Mikey tried to reassure him.

Leo didn't answer. Splinter had told him he didn't know by heart the content of every scroll in his library. Some of the mantras were rarely used, and some others overcomplicated.

_Leo?_

Had he just lost his body forever?

Donnie clenched his fists. "What was on that scroll, Leo? Please. Please, try to remember."

_I don't know. I don't know! It was just a healing mantra… I wasn't even reading it properly, and…_

Leo suddenly realized that even if he had retrieved the scroll, it still wouldn't have been enough. He had no idea which words he had used instead of the correct ones…

He would never remember.

 _I can help_ , Mikey offered.

 _How?_ Leo asked, slowly, gently. He didn't want to quench his brother's hopes that everything was going to be okay, everything would soon go back to normal…

 _I have a good memory, when I focus hard enough,_ Mikey said. _I forget things all the time, but I know that they are still there, deep inside. Do you want me to show you?_

_I… Okay. I'm listening._

Mikey carefully opened his memory to Leo, and the way it worked was nothing like Leo would have thought - all colors and music - but still, it resonated within him, and he let Mikey bring him back to the night when he had been reading a healing mantra all alone in his room, and the words were blurred…

And then he _remembered_ …

_Rizen, Pyotushai, Kiorin…_

Mikey's hands moved the way Leo's hands had been moving, and he let Leo's spirit expand through his body to give power to the words...

Somewhere, very close but also far, far away, something was screaming. _Nooooooooooooooooo! Not again!_

But Leo and Mikey went on, together, and soon Leo felt that the place was free, and he could part from his brother's mind…

 _Thanks, Mikey_ , he had the time to whisper.

Then his world became black and red, and painful…

His head hurt. His head hurt!

Leo blinked, and the light was too bright. Mikey was leaning over him, he could see... _he could see him!_ In front of him!

"Is he gone?" Mikey whispered eagerly, and Leo sat up with a groan and nodded.

"Who's gone?" Raph asked, his voice half-suspicious and half-hopeful as he came closer.

"He's gone!" Mikey repeated, beaming. "It's Leo again!"

Donnie carefully knelt next to him and put his hand against his brother's forehead.

And Leo could feel that hand, amazingly cold and soft against his skin.

"How can we be sure it's him?" Raph crossed his arms.

Leo looked at him, still unsure that it was real - that he could move on his own free will.

That he was alive.

He was alive!

The realization hit him, hard, and he almost felt like he was going to cry out of sheer joy, but then his brothers were going to worry and oh yes, his brothers, they were here in one healthy piece, and the imposter hadn't hurt them after all and he had been so worried about them and it was almost too much to handle and -

"I love you guys!" Leo said with his very own voice, before hugging them so tightly they could barely breathe.

"I really think it's Leo," Mikey replied cheerfully, returning the hug with strength.

"Mgngnn," Raph answered, maybe to show his approval. Or maybe to beg for a little more oxygen, it was hard to tell.

Donnie said nothing, hiding his face in the crook of Leo's neck. Leo wondered if he had read more about what the spirit could do than he had told them.

"My sons?"

The call startled the four turtles out of their hug, and they turned to look at their father and Sensei, who was opening his eyes and sitting down, rubbing his forehead.

"What… what is going on here?" he asked slowly, taking in the bruises on his sons' limbs.

"Everything is fine, Sensei," Mikey beamed. "Leo is back in his own body!"

His father raised an eye ridge.

"Short-term effects." Donnie sighed in relief, his arm still around Leo's shoulders. "I love that in a drug."

Splinter frowned. "Drug?"

Leo winced.

"I can explain, Sensei," he said hastily, although he had no idea where to begin.

At his side, Raph chuckled - a half-strangled, half-relieved-to-the-core chuckle - and nudged him.

"Good luck."


	13. Twitching Whiskers

"Please do so, my son."

Leo took a deep breath, gathering his thoughts. He wished he could somehow diminish the seriousness of the recent events, but it would have been lying, and he wasn't going to do that. He was in enough trouble as it was. At least he would be once his father knew the truth…

Splinter coughed, and Leo realized that everybody was waiting for his explanation. Swallowing hard, he decided to go for the most straightforward path: to start from the beginning.

"I… Two days ago, I decided to borrow one of your scrolls for - uh… night school."

His father furrowed his brow. "Which scroll was it?"

Leo resisted the urge to twist his wrist wrappings. "The one about Fracture Fixation."

Splinter inhaled sharply. "Leonardo, I thought I had been clear. I don't want you to learn this mantra."

Leo averted his eyes. He wondered if he should acknowledge that indeed, his father had been clear, or if it would only make matters worse by highlighting his disobedience. In the end, he opted for silence.

Splinter sighed. "Where is it now?"

"Uh…" Leo bit his lip. "It's there," he said, trying to keep his voice light and relaxed as he pointed at the pile of ashes on the floor.

Splinter looked at it, then at Leo, then at his other sons. Raph had crossed his arms and seemed to be waiting with great anticipation for the moment when Splinter would reduce Leo to another pile of ashes. Donnie and Mikey were listening intently, obviously happy not to be the ones having to do the explaining.

"Leonardo…" Splinter said, very slowly. The threat in his tone was unmistakable.

His father's gaze was burning him. Oh, how Leo hated to be the focus of his attention in a situation like this.

He decided it was time to speed things a little.

"I used-it-but-I-was-too-tired-and-I-missread-the-words-and-something-took-over-my-body-but-Mikey-was-there-and-sheltered-my-spirit-and-then-I-took-my-body-back-but-the-spirit-burned-the-scroll-but-everything-is-fine-now," he blurted out, looking at the floor.

There were, maybe, five seconds of heavy silence before his father reacted.

"LEONARDO!"

Leo glanced at him, and quickly averted his eyes again as he took in the expression of utter dismay on his father's face. It was a rare sight. Splinter usually managed to stay composed under any circumstances.

"I'm sorry," he whispered, rather lamely. He had nothing better, though. There was no good way to tell your father that a spirit had been parading in your body for two days and almost killed his sons before trying to steal his body.

The silence stretched as Splinter fought to regain his composure.

"Are you telling me that a spirit - possessed - your body? For two days?"

Leo nodded. "Hai, Sensei."

"And when you say that Mikey sheltered you…"

"He was in my mind," Mikey interjected helpfully. "It was nice to have him by, really."

Splinter gave him a look that clearly stated he would do better not to try to defend his brother, and Mikey grinned sheepishly before hiding behind Donnie.

"I was in his mind," Leo repeated. "We managed to communicate, and then to warn Donnie and Raph - and today, well… today we also managed to banish the spirit."

Splinter took a deep breath. "You've been luckier than I can tell you, my son," he said.

His hands were resting on his knees, and maybe Leo was imagining it, but they seemed to be a little too motionless, as if his father was fighting the urge to move them to, say, throw him across the room.

"What do you know about that spirit, Sensei?" Donnie asked timidly, his curiosity irrepressible.

Splinter sighed. "Not much." He stood up to pace around the room. "I had been warned that this scroll was for advanced students only, because it's very close to a summoning ritual, but I had never really believed that." He shook his head. "I thought it was merely too difficult, or I would never have left it with the others." He stroked his beard. "There are many beings lurking in the shadows, waiting for mortals to make a mistake so they can take their place in the world of the living. You're lucky you didn't summon one of the worst spirits."

"He wasn't that bad at first," Mikey conceded. "Except when he was trying to kill us, of course."

Splinter spun on his heels, eyes narrowed.

"Please expand on that," he ordered.

* * *

Leo felt exhausted. He had told Splinter everything he could remember, and his father hadn't spared him in the slightest, asking precise questions to make sure he had the story in every detail. Mikey had completed his tale as much as he could, as had Donnie and Raph.

Now, Splinter had his eyes closed and was taking deep, slow breaths. He didn't seem to be willing to throw Leo against the closest wall, though - maybe he considered that his son had been battered enough for the day.

"My sons. I'm grateful for your resources, and for the fact that you're all alive. Knowing what happened, I believe it's for the best that the scroll was burned. Spirits like the one you have encountered won't be able to find any of you again."

"Works for me," Raph whispered.

As Mikey nodded enthusiastically, Splinter looked gravely at Leo.

"Leonardo, come with me. I wish to talk to you in private."

Leo didn't miss his brothers' sympathetic glances as he stood up and followed his father inside the dojo.

He was so doomed.

He knelt in front of his father and hung his head in shame, waiting for Splinter's lecture.

"I am disappointed in you, Leonardo."

Leo had expected the words, but they hurt nonetheless.

"I'm sorry, Sensei."

"The results of your mistake could have been dire."

"I know, Father," Leo whispered, his throat dry. Thinking about what could have happened to his beloved family - a family he was supposed to help protecting, by the way - made him sick.

"Although you're not the only one responsible. I should have taken the warnings I've been given concerning the scroll more seriously, and warn _you_ as a consequence."

Leo raised his head, surprised. His father wasn't entirely blaming him for the recent events?

Splinter half-smiled before going on. "Concerning your wish of… well… _night school,_ I am willing to help you. If you are that eager to read the mantras when you're so tired that you can't think straight, I can teach you how to stay focused even in this state of mind. Let's say, every two days for as long as it will be necessary."

Leo stifled a sigh. He knew what it meant. His father would make sure to exhaust him before they even came to the lesson of the day - this was going to be painful.

He wasn't going to protest, though. The day could have ended much, much worse. "Hai, Sensei."

"And," Splinter added, his voice louder, "if one of you wants to join your brother, you only have to keep spying."

Leo turned around just in time to watch a trio of heads disappear from the dojo frame. Splinter smiled slightly.

"Now, tell me, Leonardo. Why couldn't you wait to learn that mantra?"

Leo tried to remember his reasons. They seemed ridiculous now. "I… I didn't understand why you refused to teach me, and I needed…" He swallowed hard. "It's important knowledge."

Splinter tilted his head. "We would have come to it eventually, my son."

"But maybe not soon enough!" Leo exclaimed. "We never know what can happen, or when you… or if…" He shut up, at a loss for words. How was he supposed to tell his father that he would never take him for granted again? With the lives they led, anything could happen. What if they were separated from him again? Leo needed to prepare for that. He needed to learn as much as he could, as fast as he could…

Splinter considered his son for a long time. When he spoke again, his voice was strangely soothing, with maybe a hint of regret.

"Leonardo. I am aware that I have left you and your brothers on your own for way too long."

Leo bit his lip. "I didn't mean to…"

"I know, my son," Splinter cut him off gently. "And I'm grateful that we are together again. But, Leonardo, you need to trust me if you want my teachings to be as efficient as they can be."

"Sensei, of course I'm trusting you!" Leo protested. He didn't understand. Why would his father think the opposite?

Splinter held his gaze for a long time before smiling - and maybe Leo was imagining the hint of sadness in it. It had been a long day.

"Very well, then. Now go join your brothers. I'm sure they're worried about you."

Leo bowed and left the room, still unsure of what had just happened. He didn't wonder for long, though - soon Mikey was bombarding him with questions, and Donnie was asking if he could check him up, just in case, and Raph was punching him from one side and hugging him from the other.

He was back where he belonged.

* * *

**Epilogue**

Leo gritted his teeth to keep the pain at bay. The Footbots that had attacked him and his brothers on their evening patrol were defeated or scattered, but his arm had hit a dumpster while he crossed swords with one of them and it hurt.

Leo glanced left, then right - Raph was bragging to Mikey, while Donnie was looting the robots for spare parts he could use in his own inventions.

The course was clear.

With swift gestures and whispered words, he began his favorite healing mantra - one he mastered.

"Rin…Pyo…"

"Leo, what are you doing?"

Leo raised his head to look at a rather panicked Raph. His brother had given up all pretense of boasting and was running towards him, with Mikey in his wake.

"Healing myself?" he answered, his voice already resigned.

"Uh, do you think it's absolutely necessary?" Donnie was approaching too, and his tone was clearly anxious. "Don't you want to wait until we're at the lair? With Splinter?"

"Guys, it hurts," Leo pointed out.

His brothers grimaced. Given how rarely he complained about things like that, they had no doubt it was serious.

"I have painkillers," Mikey offered, clearly hoping that Leo would take the offer.

"Come on, guys," Leo protested. "I know what I'm doing!"

His brothers' expressions were doubtful at best, and he really couldn't blame them. It had only been a few weeks since the whole ordeal with the stranger spirit.

"Okay. Painkillers it is, then."

"Good choice, Leo." Raph patted him on the shell with a relieved expression.

As he gulped the pills, Leo wondered how long it would take before his brothers trusted him again with the healing hands.

Oh well. At least he still had a body to heal.

**The End**

**Notes for the Chapter:**

> _And the story is complete!_   
>  _On a side note, I have been wondering why Leo didn’t use the healing hands more often in the show. It’s a very useful ability to have. This is in part what prompted this plot bunny._   
>  _Thanks to everyone who supported me on this! You’re all awesome._


End file.
